There is a section of the forum for multi-channel.
https://forum.audacityteam.org/t/multi-channel-recording-in-audacity/15644/1
In order to get maximum compatibility and customers, mixer makers configure multi-channel as groups of stereo. You’re much less likely to send the mixer back if it does something. I think you’re expected to run the makers custom software to get multi-channel.
There is one odd problem. Audacity doesn’t support ASIO software packages. So if the mixer uses ASIO to get their tricks, that’s not ideal.
Koz