As far as I can tell, in an unaccelerated stall, the IL-2 P-38 has no tendency to 'flip over' if you keep it straight: This is stick full back, sinking like a stone, but staying level:
In an accelerated stall (a tight turn for instance), it will 'flip' if you pull really hard, but there is ample warning from buffeting.
I doubt if a modern pilot flying a P-38 would treat it sufficiently roughly to make it 'flip', at least intentionally.