If it's just a decal being smacked onto a hat, it should be no problem at all. Decals have to be approved before they're allowed in the system, so if it's literally just placing a decal onto a hat then that'd be simple from a moderation standpoint.
The issue with this idea, though, is that when you put a Decal on a Hat object, it mixes the texture of the decal with the texture of the mesh of the hat. It'd require retexturing the hat to get a group logo onto it. |