VRchat is a requirement, as it's a model for the game, though you could also import it into blender or use it as a personal project for a Vrm and mod it into other games.
Itch.io is usually geared toward indie games , vrchat content creators were usually selling over on Gumroad for a long time until a NSFW ban hit Gumroad, alot of content creators went to itch because they allowed adult content , I will take some time to try and badge my avatars to make it more clear what the assets I develop are ! have a great day ^>^