Ryan Quellet put up a very interesting youtube video in 08/22 showing him connecting his HD Zero VRX to his Quest 2. He believed he was getting around 70ms of latency, rough for HD Zero, which should see more like 14ms - 20ms of latency.
I'm unsure if the app has just been updated a bunch since he made the video, but the lastest versions of the APK (found in the video description originally) work really well.
I tested this myself using a Walksnail Avatar HD V2 kit and saw 14ms of latency added on top of the ~30ms of latency the Walksnail VRX creates on its own in the default settings.
The setup used to get those results was :
Walksnail VRX > HDMI mini cable to HDMI > HDMI to USB C adapter > Quest 2. I painters taped the VRX to the Quest 2 and put a battery in my pocket for the VRX.
On the Quest 2 I use this APK that I found from Ryan Quellet video description above. Literally just plug and play from there!
If you found this helpful or have feedback/suggestions, let me know at openuasdev@gmail.com