Is there a self-hosted web-based VR “space” software like Decentraland?

I think the NFT and social aspects of Decentraland are cringe, but I think the software works very well to visit a 3-d "land" on desktop and mobile.

I'd like to make a small pavilion to represent an art gallery, theme park, or a real place. I'd like to be able to run it on my PC for testing and then later in the cloud. I don't need multiplayer but I'd appreciate NPC's (I like the character animation in the Unreal framework but I'm not sure if that is feasible)

Extra points for WebXR support for headsets or for that matter "magic window" (ARCore) functionality with phones.

Is there any preexisting application or framework for this?