So, DH Hornet propellers rotate In at the top, same as the Twin Mustang (with the exception of the 1st one).
P-38’s all turn out at the top (again, with the exception of the first one)
In the case of the 82 vs the 38, I think the relative position of the wing vs the centre of the prop arc must have something to do with it.

Anyone have any thoughts, or god forbid, facts!:D

I understand that engine failures in the Twin mustang were pretty much a non event, whereas the P-38 took some very quick and specific handling to maintain control after losing an engine.
This makes sense with regards to torque.

Andy

Aerodynamically there must be a good reason for wanting the propellers rotating towards each other at the bottom, as several manufacturers have attempted it in the first place.

I don’t know the answer, but wonder if someone does?