Create a new project and add these VCC Packages one by one.
VRChat Package Resolver Tool, VRCQuestTools, Poiyomi Toon Shader, VRCFury and Avatar Limb Scaling.
MAKE SURE THE VERSIONS MATCH THE ONE IN THE PICTURE.

After adding these packages, open the project, add the Avatar Unity Package, and make sure everything is correct and to your liking.
Go through each material and turn the shader from "Hidden/Locked" to "Poiyomi Toon."
Before uploading, review any alerts and auto-fix anything that needs auto-fixing.

If all of that does not work, try reopening the project after doing all of these things.