It should be able to generate Air spawns for both sides... still, they will end up some km's from each other, in this attempt 15km:
Dogfight mission attached here ..
One could try and find airfields closer together, on some map, in some time frame... You can browse through all maps and towns in the Generator
I bet it'd be easier and faster to ask on the Sturmovik forums whether a mission builder can do it for us: Should not be too difficult for an experienced builder now should it?
SYN_Generated.mission