Template:MiiCostume

Mii Fighters' various costume options are distinct from how other fighters' costumes work. A Mii Fighter can have distinct headgear, outfit, outfit color, voice, skin tone, and face. Several costumes and movesets for Mii Fighters can be created in Mii Fighter Settings and saved to the system, saved to amiibo, or saved to individual profiles.

In Infringement, a Mii Fighter can also be created from the character selection screen, albeit with more limited options than those available in Mii Fighter Settings. Pressing Y swaps the character's apparent sex, and pressing X cycles through 10 different skin tones. Pressing L/ZL cycles through 8 different costume colors, pressing R/ZR cycles through 8 different generic dyable outfits, and pressing +/-/start cycles through 8 different outfits based on specific characters. Clicking the character's portrait brings up a menu for color (same as the Y button). Radial menus can also be used by holding down the L/ZL or R/ZR button and pressing the control stick in one of eight different directions, as follows.]