Every character in Super Smash Bros. Ultimate gets eight different color variants that give players a chance to customize their selection a little bit based completely on aesthetic preference.
This option is mainly used as a way to let players change how their characters look during matches, but Byleth and Hero both provide more representation from their franchises. It is also a way to distinguish who is who during matches where two players are using the same character.
Because Byleth is the only representative from Fire Emblem: Three Houses, they are pulling quadruple duty by providing fans of the series a chance to represent any of the three available houses, and a few other hints that Masahiro Sakurai wanted to include.
Here is an explanation for each of the skins based on knowledge from Fire Emblem: Three Houses.
|Base Male||The standard male design for Byleth from the start of the game.|
|Base Female||The standard female design for Byleth from the start of the game.|
|Blue||Based on the color scheme of Dimitri from the Blue Lions house|
|Red||Based on the color scheme of Edelgard from the Black Eagles house.|
|Yellow||Based on the color scheme of Claude from the Golden Deet house.|
|Green||Based on the color scheme of Sothis, or the goddess living within Byleth who appears in their Final Smash.|
|Black||The male design for Byleth after fusing with Sothis later in the game.|
|Grey||The female design for Byleth after fusing with Sothis later in the game.|
Byleth is the final character being added through the first wave of Fighters Pass DLC, but six more characters are on the way in Vol. 2, which will start releasing characters sometime after the professor releases on Jan. 28.