I beleive its the mark of the Zero, A6M2, A6M3 all have diffrent wing shapes because of the design on how best to fit on the carrier deck, some retract, some dont (the A6M3 has a smaller wing shape and doesn't retract) whereas the A6M2 has a longer wing and folds (one section, not the whole wing itself, just the tips fold in so it can fit easier on carrier decks)
I hope that helps
Only the A6M3 Model 32 had "Clipped" wings, all other versions had the rounded wing tips. Earlier A6M2 had wider span with folding wingtips to fit the carrier deck elevators, while the later A6M5 had its span reduced to the same as the clipped A6M3 but the outer wing area was restructured to the rounded tips.
A6M2 folding wing tip. This particular piece is from #4593 recovered from the Aleutians in 1942 . . . yes, that A6M2. An overall and a close-up of hinge detail. Note the mix of US and Japanese undercoatings. The US was applied when the A R folks in San Diego repaired the rib and the dished in underside in the summer of 1942 restoration. Rather a hasty slap on with a paint brush job.