Both scenarios make sense from a 'soul searching' perspective, I suppose. We can't go by the hair.

I do wonder if they're not positioning Yelena as another Black Widow for the future MCU.

You should never be jossed. We should strike that word from the fannish vocabulary because of what a shithead he was revealed -- and revealed himself, without shame -- to be. But you can very much still be russoed if you pick a timeframe, especially because I'm pretty sure the MCU has dropped cross-movie continuity after Endgame.