"You have to go to the domestic airport."
Maybe the better English translation would be "You guys have to go to the domestic airport"。
Technically in English "you" can mean a group of people too, like the German "Sie".
Whilst 'you guys' is certainly used in some dialects of spoken English it's very informal so it would almost certainly not be used in this context (i.e. a transfer desk employee instructing passengers how to reach their gate.) I think most would agree that amongst the many possible variations in any given translation the one closest to standard English is the preferable one, not a slangy colloquialism used by some speakers in certain areas.