Basically, we took his model from smash ultimate into blender, made his textures into more solid colors and applied a shader to the model that makes him look the way he does now. After we got the model set up, we applied an animation file from smash ultimate and have Blender render that animation into an image sequence, this is repeated for each of his animations and custom animations are made when needed.

There's much more to the process than what I've explained here, but I think this the best way to sum it up.