The latest version for PC is v0.9.7 (October 2023), the latest version for Quest standalone is v0.10.1 with Passthrough,chroma key masking.

The PC version with Passthrough,chroma key masking,etc, I don't think it will be available for a few months.

The passthrough update is now available on the Steam beta branch for PC. To switch to the beta branch, go your steam library, right click on HereSphere, go to properties, betas, and then select beta - beta test. No code is needed. It currently only works in conjunction with Virtual Desktop's passthrough feature. You can view the Steam release notes for more details: https://store.steampowered.com/news/app/1234730/view/3995323572396915359

Yes, it's a planned feature. Currently finishing up Apple Vision Pro port, and will work on the UE5 update after that.