Super Smash Bros. Ultimate Ripping Project

[Darkliger01]

I just took a look into the Mii's files and I found it only has their costumes, how do we get the actual bodies?

I'm not sure, but I think there might some model data for the Miis within the Switch itself (same with the systems before it), and games like Mario Kart and Smash take the Mii faces from there.