Should have said "custom", but then that could also be misunderstood.
In my experience (I made the first VR MMO: http://aeonalpha.com, with the wrong programming language!) high refresh rates in sensor reading (faked by Oculus/Valve) combined with locomotion that the brain does not immediately associate with human motion are the best solutions after hardware.
But I will make my 3D action voxel MMO 3rd person just to make sure, if your head is the camera you wont get sick as easily, specially at 120Hz.
120 FPS at low persistence is the bare minimum if you want to not get ill from any smooth movement during long sessions = Echo VR is the ONLY game that is playable on Quest 2.
Non-smooth movement games are more of a slideshow/shooting gallery; (see HL:A :S) akin to the early fixed space 3D games on cd-rom if you remember those, which funnily HL was the first (after quake that I never played) to break:
I fondly remember me and my brothers jaws dropping simultaneously when we by mistake moved the mouse during the intro, we both 100% thought it was pre-rendered.
The difference is now we have permanently peaked in hardware, so we need to solve things with software.
I haven't tried "Tea for God" yet, kinda dreading the adb install since computers can get bricked when you do real work on them these days.
Baffling that in 6 years, 1 billion humans (that could have bought a headset and built something) only managed to create 3 custom engines for VR: Source 2, Lone Echo and "Tea for God".
Odds are not looking good.