There are software routing apps that work within macOS that are phenomenally good. You just route audio from app A to app B in software, no wiring or fuss.
I can't go into detail right this very instant, but if you're in a hurry, you can do some research on your own! The best products for this, by far, are the ones from Rogue Amoeba: research Audio Hijack
to learn what they can do. I use both, but honestly I have found that Audio Hijack does nearly everything I need. For your specific use case, I'd need to look and see if I can create an AH routing that will do what you want; Loopback will definitely do it.
Loopback is the currently supported version of apps like Soundflower from the olden days. They were free but were abandoned as Apple got more invasive of how routing worked; these guys have you pay money, but when you buy their apps you can be sure they'll do what they say on the label.