Passing in the trans sense of the word is passera in Swedish, I'm not sure about passing as a specific person. If you speak about getting into events with age limits of different kinds, people would usually just speak about komma in instead (like, when they let you in to see a movie where the age limit is 15 but you're only 13).
genom only means 'through' as you could pass through a city or doorway. It's possible to add förbi in Swedish here but we're more likely to say just passerar vi (even in many cases where you'd want 'by' in English). On the other hand with verbs like går förbi or åker förbi (like, 'walk by' or 'drive by'), of course förbi is absolutely necessary to get this meaning.