It should work exactly like modding Brawl or Project M. You'll need BrawlBox, which you can get on kc-mm, and you can simply replace textures as normal.
Unless BrawlEX fucks everything, but I don't think it does.
Yeah, there should be nothing unique about texture replacement in Minus. Either use bbox to import textures and such or drag and drop the Fit0X files you need into their respective folders.
I wanted to add costumes not replace them. Well I did find a way (cBliss) and try to apply it to brawl minus, but the costumes won't show. I follow the tutorial and everything and still no luck.
