Exactly. It seems this was possible with XIM Apex based on the remote play guide in the forum so I assumed it would be the same here which appears to not be the case.
I don't think it's officially supported but I've been playing Forbidden West(Horizon PS4 St) since release with the Nexus via remote play on PC. Using main display from PS5 of course.
This is how I've set it up, doesn't always work 100% but gets the job done most of the time.
- Log into PS5
- Turn Off DS
- Make sure Xim Nexus is unplugged from PC
- Open PS Remote Play App and connect
- With DS connected to Nexus, Turn on DS then plug Nexus to PC
- Profit
With PC's there are so many variables but also make sure no other controller is connected/plugged in.
Give that a try.