I don't think there is enough activity or demand for something like that. People sometimes share games they've placed of course but it's usually just a post in the relevant games main forum. Fanfiction and other fan creations are encouraged but again we don't really see enough demand for a dedicated area.
If demand is low, would it be visible to more people if I put it here, on Steam, or on Discord? Or is there yet a more appropriate platform?
Good to know that I will just put it in the main forum then, if I end up doing this. Still a bit burned out from my Stellaris one on Paradox.