"Hybrid" GPU passthrough

Hi there!
I am using Manjaro KDE now since a few weeks and I am really really enjoying it! But since I do gaming, too I still use Windows Dual-Boot which I would like to get rid off.

I want to be able to use my Vega 56 on Linux AND pass it through a guest VM if needed while still having the host on my second monitor connected to a second GPU (HD 5450 atm).

I have seen a video on YouTube where one guy is loading/unloading the driver to his card (single GPU) on demand when starting/stopping the vm. He is doing this with Fedora and doest stop/start the sddm.

Will this be possible on Manjaro KDE but with the difference I mentioned to be able to use the guest on one GPU and the host on the other GPU at the same time?

I am willing to fiddle around with it but I’am still new to (this kind of) Linux (tweaking). So would be very helpful for some advice which tutorial or similar to follow and what to change due to my specific need (if needed at all). I just don’t want to invest plenty of time just to figure out at the end it’s not possible at all.

Thanks for every tip! =)