itch.io

https://github.com/greenheartgames/greenworks/blob/master/docs/workshop.md

I just noticed that greenworks provides relevant documentation.

I actually don't think this helps as it requires solving two problems at once.

1. When a user subscribes, the content needs to appear in the game subdirectory.

2. When the user unsubscribes from the item, it needs to be removed (still a subdirectory)

All in all, this is almost impossible for RPG makers.