Japanese didn't have winter camo like the Germans did. [edit: I mean like the whitewash camo that wore off -- come to think of it I don't recall seeing any winter camo for any IJA/IJN planes at all!]
It's white with some areas of silver showing through.
If it were green flaking off, the only thing showing would be silver, and it's clearly white (not silver). So it's an A6M2 fighting an F4u1 (1A?). It'd be like having a P-51D diving on a 109E-3. They're just from different eras.