Unity recently released a new VR Multiplayer template (for Unity 6), which makes it real easy to setup a multiplayer VR application. They included all the default interaction methods, so you can grab the example scene and throw in some of your own content using the provided examples.
We are adjusting it for our own project to work for simple MR examples as well, which (for Quest 2/3/3s) requires changes in:
- SDK, add OpenXR Meta and Enable Passthrough
- Scene, remove background visuals and enable passthrough camera
- Player visual, you’ll need to adjust the player visual
- Spatial Localization, we ask the user to manually define a shared location in the space, but you could use the Meta Shared Spatial Anchors if you stick within the Meta ecosystem.
VR Multiplayer Template Quick Start Guide | VR Multiplayer | 2.0.3 (unity3d.com)