Alternate costume (SSBM)

NOTE: Every claimed source needs a cross-reference link; claimed sources need to be plausible, not horrendously obscure; default costumes usually don't need descriptions since they are not alternate costumes; returning costumes original to Smash do not need references to their appearances in previous Smash games.

Super Smash Bros. Melee added additional alternate costume options to characters by using the X and Y buttons to cycle through the available list instead of using four C buttons to pick a specific color; this removes the limit as to how many are selectable, so there are no longer any costumes exclusive to Team Battles or computer opponents. As a result, many characters now have five different color schemes, with some having as many as six, though some still only have four.

When selecting characters in tournament mode, instead of displaying the character's colored image of the chosen costume, the character's name is given a tint and a colored bar is displayed in the player list. This color is usually an intuitive indicator of which costume has been chosen (with no color denoting default), but there are some that are slightly unusual (such as Luigi and Peach's white costumes that are denoted by a grey).

In Team Battle, if members of the same team use the same character, the second player would have a lighter tint applied to their character. A third player uses a darker tint. If a fourth player is forcibly added to a team with the Name Entry glitch, then the fourth character will be completely black; the game's data suggests that a fifth player, if possible, would be completely grey. A sixth player and afterward, would crash the game.

Strangely enough, alternate costumes can affect gameplay, such as Captain Falcon's model changing sizes depending on the costume.

Bowser

Green	G
Red	R	Resembles a Spiny or red Koopa Troopa. It also resembles Roy Koopa's early in-game sprites without the sunglasses, as well as Bowser's second player costume in Mario Golf. Unusually, while the artwork depicts Bowser with red eyes, they are green in-game.
Blue	B	Came from Bowser's Japanese artwork for Super Mario Bros. Also resembles Iggy Koopa's early in-game sprites. Sometimes referred to as the "fake Bowser".
Black		Based off of Morton Koopa Jr.

Captain Falcon

Indigo
Black		Based on the colors of his outfit from the Japanese F-Zero X commercial.
Red	R	Based on Falcon's rival, Blood Falcon's outfit, even altering the logo on his back to say "Blood Hawk". Betas for the game show that it was originally intended to read "Hell Hawk", the Japanese name of Blood Falcon's F-Zero machine.
White		Based on the colors of Jody Summer's outfit. Commonly known as "Captain Fabulous" in the community.
Green	G	Based on the colors of Pico's outfit.
Blue	B	Based on the original, lighter colors of Captain Falcon in F-Zero.

Donkey Kong

Brown
Black		Resembles Donkey Kong's coloration when Donkey Kong '94 and Donkey Kong Land were played under the black-and-white palette on the Game Boy Color and Super Game Boy. "Monkey Smash" mode in Donkey Kong 64 also featured Donkey Kong with blue-black fur and a blue tie.
Red	R	Resembles Donkey Kong's sprite in Donkey Kong.
Blue	B	Similar to the second player coloration in Mario Golf.
Green	G	Similar color scheme of his arch-rival,King K. Rool, with the green fur and red tie to match King K. Rool's green scales and red cape.

Dr. Mario

White		Despite wearing white pants in his own game, Dr. Mario wears indigo jeans in Melee.
Red	R	Resembles Nurse Toadstool's color scheme.
Blue	B	Resembles the traditional color of scrubs worn in real-life hospitals, while his violet gloves resemble standard nitrile gloves used by most physicians.
Green	G	Resembles the traditional color of scrubs worn in by real-life surgeons.
Black		Referred to as the Unlicensed Doctor by the official Melee website.

Falco

Tan
Red	R	Resembles Peppy Hare's flight suit from Star Fox 64
Blue	B	Resembles Slippy Toad's outfit from Star Fox 64.
Green	G	Resembles Fox's flight suit.

Fox

White
Red	R	Resembles Falco's flight suit from Star Fox 64.
Blue	B	Resembles Slippy Toad's flight suit from Star Fox 64
Green	G	Possibly based on concept art for the original Star Fox.

Ganondorf

Brown		Based somewhat on his model from the Nintendo Space World Demo for the GameCube.
Red	R
Blue	B
Green	G
Purple

Ice Climbers

As can be seen in the image, the Ice Climbers' orange and red costumes will place Nana in the lead, making Popo follow.

Blue	B
Green	G
Orange
Red	R

Jigglypuff

Pink
Red	R
Blue	B	Similar to the bows from the original Super Smash Bros.
Green	G
Yellow		The crown that Jigglypuff wears in this costume is identical to that worn by Peach.

Kirby

Pink
Yellow		This color swap is Keeby, who was Kirby's companion in games that featured co-op mode. It is also the same as when he is Beam Kirby or Needle Kirby, without the hat. It was also an alternative palette for Kirby in the multiplayer for Kirby 64. Developer Shigeru Miyamoto also reportedly believed Kirby should be yellow in his debut game, while Masahiro Sakurai believed the character should be pink.
Blue	B	Resembles Ice Kirby, without the hat. It is also an alternative palette for Kirby in the multiplayer for Kirby 64.
Red	R	Resembles Fire Kirby, without the hat.
Green	G	An alternative palette for Kirby in the multiplayer for Kirby 64.
White		A reference to his monochrome appearance from the original Kirby's Dream Land for Game Boy. It is also similar to the colors of Kirby's depiction on the North American box cover of Kirby's Dream Land.

Link

Green	G
Red	R	Based on the Goron Tunic from The Legend of Zelda: Ocarina of Time. It also resembles Link with the Red Ring from the original The Legend of Zelda.
Blue	B	Based on the Zora Tunic from The Legend of Zelda: Ocarina of Time.
Black		Based off of Dark Link.
White		Resembles the use of the Blue Ring in The Legend of Zelda.

Luigi

Green	G
White		A reference to Luigi's appearance in Super Mario Bros. and the NES port of Mario Bros. It also resembles Fire Luigi. It is the only one to change the color of his gloves and skin tone.
Blue	B	Resembles the artwork for Mario on the cover for the NES version of Mario Bros., though with darker overalls and a light blue hat instead of a blue one.
Pink	R	Based on Luigi's appearance in Wrecking Crew, though Luigi wears a pink hat and not a red/pink one.

Mario

Red	R
Yellow		Based on Wario, the same as his yellow costume in the previous game. Unlike the original (and every other iteration in the series), the colored "M" is blue instead of yellow and the buttons are white instead of yellow, as to make him more closely resemble Wario. Additionally, Mario's hat gains a white accent on its edge.
Black		A reference to Foreman Spike from Wrecking Crew '98. Updated from the original version of this swap to be closer to black and white than brown and yellow. It is the only costume where the hat and overalls are changed to be the same color.
Blue	B	A reversal of his traditional colors. This is seen as a partial reference to Mario's varying appearances in games prior to Nintendo's official establishment of Mario's outfit consisting of a red shirt, blue overalls, and red hat. In various earlier games, Mario occasionally also appeared with a blue hat, red shirt with blue overalls, or a red hat with a blue shirt with red overalls. Interestingly, though, Mario never appeared in any game with the particular combination of a blue hat, blue shirt, with red overalls as it appears here, but this color scheme does resemble the Balloon Fighter and it also resembles Mario's outfit from the DIC cartoons.
Green	G	Complimentary colors of his normal outfit. Resembles Mario's appearance on Japanese and European box arts for Wrecking Crew, but with a green hat instead of a orange one. A similar arrangement of colors also appears as part of the flashing animation from a Starman in Super Mario Bros. Updated from the original version of this swap to have overalls more brown than orange.

Marth

Blue	B
Red	R	Based on the standard color for enemy units in Fire Emblem games. This is the only costume in Melee to change the color of his circlet.
Green	G	Based on the standard color for NPC units in Fire Emblem games.
Black
White		Based on Leif, the protagonist of Fire Emblem: Thracia 776 and a character from Fire Emblem: Genealogy of the Holy War.

Mewtwo

Purple
Red	R	Resembles one of Mewtwo's possible alternate color shades in the Pokémon Stadium games.
Blue	B	Resembles Mewtwo's in-game sprite colors for Pokémon Red & Blue. Also used as an Easter egg in Pokémon Stadium.
Green	G	Based on Mewtwo's shiny color in the Pokémon games.

Mr. Game & Watch

Black
Red	R
Blue	B
Green	G

Ness

Red	R
Yellow		The yellow/black color scheme resembles that of the Hanshin Tigers, a Japanese baseball team. The shirt also bears a very similar color scheme to the Gigantic Ant enemy from EarthBound.
Blue	B	Is based off of Ness's younger self that he encounters briefly in Magicant, who was wearing a blue hat.
Green	G	Resembles the color scheme of Everdred.

Peach

Pink	R
Yellow		This costume changes Peach's entire appearance to that of Daisy, including her hair color, earrings, dress style, gloves, tiara, and even skin color. However, later games in the Mario series changed Daisy's design, resulting in the costume only matching games before Melee. It is the only alternate costume to change Peach's hair and skin color to brown.
White		Represents how she appeared in her first appearance in Super Mario Bros, without the red hair and red trim. Peach uniquely wears pantyhose with this costume.
Blue	B	Based on a swap from Mario Golf, and Daisy's appearance in NES Open Tournament Golf.
Green	G	Based on a swap from Mario Golf, and NES Open.

Pichu

Yellow
Red	R
Blue	B	Gives Pichu goggles similar to the Swimmer class of the Pokémon series.
Green	G	Gives Pichu a backpack that resembles Ness's. Pokémon Trainers throughout the Pokémon series also wear backpacks.

Pikachu

Yellow
Red	R	Has Pikachu wearing the hat of Red, the protagonist of the Generation I Pokémon games. The fur color also resembles that of Pikachu's shiny coloration in the Pokémon games.
Blue	B	Similar to the party hats from the previous game.
Green	G

Roy

Purple
Red	R	Based on the standard color for enemy units in Fire Emblem games.
Blue	B	Based on the "player" unit color in the Fire Emblem series. Is the only alternate costume to change Roy's golden trim color.
Green	G	Based on the standard color for NPC units in Fire Emblem games.
Yellow

Samus

Orange	R
Pink		Based on the color scheme of the Varia Suit when missiles are selected in the original NES Metroid game.
Black
Green	G	In Japan, the original Smash 64 website referred to this alternate costume as "mass produced Samus".
Purple	B	Based on the Gravity Suit.

Sheik

All of these colors go with Zelda's costume and come from the same game as Zelda's.

Navy		Corresponds with Zelda's pink colour, hence why it isn't used for team battles.
Red	R
Blue	B
Green	G
White		This costume is the only one which changes Sheik's skin tone.

Yoshi

All of Yoshi's costumes appear as different variations of the Yoshi species in many of his games, such as Yoshi's Story and Super Mario World.

Green	G
Red	R	Based on the fire-breathing Yoshi in Super Mario World.
Blue	B	Based on the flying Yoshi in Super Mario World.
Yellow		Based on the stomping Yoshi in Super Mario World.
Pink		Based on the Pink Yoshi from Yoshi's Story.
Cyan		Based on the Light Blue Yoshi from Yoshi's Story.

Young Link

All of Young Link's colors are exactly the same as Link's, except ordered where the black and white costumes are switched.

Green	G
Red	R
Blue	B
White
Black

Zelda

Pink
Red	R	Resembles Zelda's sprite in The Legend of Zelda if Link possesses the Red Ring. Also resembles Zelda's appearance in Zelda II: The Adventure of Link.
Blue	B	Resembles Zelda's sprite in The Legend of Zelda if Link possesses the Blue Ring. Also resembles Zelda's maiden outfit in The Legend of Zelda: A Link to the Past.
Green	G	Resembles Zelda's sprite in The Legend of Zelda if Link possesses neither rings.
White		Resembles Zelda's field sprite in The Legend of Zelda: A Link to the Past.

Stats

There is a total of 123 alternate costumes.
The average number of costumes per character is 5.
Captain Falcon, Kirby and Yoshi share the highest amount of color swaps: 6.
There are 10 fighters with 4 color swaps, and 13 with 5.