Short backstory, I was using Linux as my only OS for a few years, but as we all know Linux is not the greatest when it comes to games, so about 2 years ago I switched to Windows, in the meantime I upgraded my whole audio setup, but now I would like to switch back or between Linux & Windows.

Currently I am using a ESI U168 XT audio interface to connect my mixer with my PC:
- 4 stereo channel from PC to mixer (8 1/4" TRS cables)
- 2 stereo channel from mixer to PC (4 1/4" TRS cables)

The audio interface makes all channels directly available in windows, and since windows 10 that means I can easily route specific applications over specific channels, and that is exactly what I need, here a screenshot:

My problem now is that the ESI interface does not support Linux, from what I have tested it doesn't even get recognized in Linux.

Now I was looking at the Fireface UCX, which apparently has a class compliant mode, so it should work in Linux?

But does this interface work as I want it to work?
Can I use all channels in Windows directly?
Can I use all channels in Linux directly?

If not, any ideas are appreciated and either way, thanks for any help