Engine can’t be limited as it has two mono busses for each stereo MTX/AUX/GRP & applies panning from the channel to those busses. There is going to be simple pan law math involved to do the calculations. Splitting the busses into two mono busses would be simple programming.
Doing that for all MTX/AUX/GRP for a console of this price range, debatable. (But we all would love a 24 mono aux capable console).
Doing that for the MTX only, necessary IMO.