Not exactly what youre looking for, but this type of game (using relavistic physics) has been attempted. Heres one built in unity that could be easily ported to a Quest line device.

https://en.m.wikipedia.org/wiki/A_Slower_Speed_of_Light

I also found this render (and game!) that show off some aspects of relativistic spaceflight. https://youtu.be/Ix1XlxF66Zk?si=8HzDH3U-CRM-erRB

I think the technical limit might be moot, better question might be how strong of a stomach you have, geometry gets pretty wacky near c