I can understand that. I used to do a lot of game streaming with Parsec and ended up with a similar setup.

Right now, TOMMY only use Wi-Fi and doesn't support using ethernet for the communication with HA and Wi-Fi for peer-to-peer communication. But that is very possible to implement. Just haven't encountered the use case before now.

I'll probably implement an option for split communication (ethernet, wifi) and then allow users to decide the Wi-Fi channel devices communicate on peer-to-peer. That way you'd have full control over possible interference.