Will makes a good point, it can be done.
However, you are having other issues as well.
RME is famous for its drivers. Their mic pres are also highly regarded for their transparency.
I don't think you can go wrong with RME; the downside, you get what you pay for and top value = top price.
I have the original Babyface in my office and the UFX+ in the studio (ran the original UFX for 9 years).
I've never tried to use both at the same time, but they use the same USB driver, so I suspect that I could.
You mentioned that you enjoy the "knobs" on the Behringer. Its all "virtual" with RME.
TotalMix takes a bit of use to wrap your head around, like any "desk" does, but once you do, its great and beyond "versatile".
I suspect it will do everything you need and more....
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