Full Idea
If the Socrates of the actual world has snubnosedness but Socrates-in-W does not, this is surely inconsistent with the Indiscernibility of Identicals, a principle than which none sounder can be conceived.
Gist of Idea
If possible Socrates differs from actual Socrates, the Indiscernibility of Identicals says they are different
Source
Alvin Plantinga (Transworld Identity or worldbound Individuals? [1973], I)
Book Reference
'The Possible and the Actual', ed/tr. Loux,Michael J. [Cornell 1979], p.150
A Reaction
However, we allow Socrates to differ over time while remaining the same Socrates, so some similar approach should apply here. In both cases we need some notion of what is essential to Socrates. But what unites aged 3 with aged 70?