not a good idea. Different performance makes formation a sweaty affair
I have multiple hours of formation flying in my T-6 and in small RV type airplanes mostly same type flying which is a piece of cake but requires practice.
I was asked to bring my IV-P for a funeral of a close friend and the rest of the formation included 3 T-6, will never do it again i was in the middle trying to avoid stalling the entire way with flaps down and still could not get slowed down enough to keep pace (and I have about 400 hrs of formation flying).
so not recommended, get same type airplane or same performance to do formation.

ak