By the way, the avatar's buttons are broken and the clothes don't change.
Viewing post in Aririal 3d VRChat avatar comments
The technique I use for outfit toggles is called UV Discard, and is exclusive to Poiyomi toon shader. By my testing, and on the public avatar, it seems to work fine. The official documentation is here: https://www.poiyomi.com/special-fx/uv-tile-discard/