Not currently, no. It's been asked for as a feature request before, so the team is aware of the desire.
I could lie to you, if that would make you feel better.
I have a Nintendo Switch set on a 5.1 setup, however I can only use a stereo signal out to Sonos. After re-configuring my surrounds (a la
remove and re-add), I was able to achieve a similar effect to what you were looking for.
In this case, I selected the furthest distance when it asked how far my surrounds are from my "seating area". This causes Sonos to pipe in a little more to the surrounds (since it thinks its further than it actually is) allowing you to get a similar "dual-stereo" effect in smaller environments. While it may not be a
perfect solution, I know I'm definitely enjoying MarioKart a little bit more. 🙂
Hope you find this helpful!
Just to add to Keith's solution, in the App's PlayBar 'room' settings, goto 'Advanced Audio/Surround Settings' and try adjusting the TV Level slider bar to see if that also helps get a little more audio out to your surrounds.