On the Nebuchadnezzar, other than the two naturally born humans Tank and Dozer, were any of the crew ever in Zion before they unjacked Mr. Anderson to join them? I think Morpheus must have been in Zion once or multiple times since he was the captain, he was rather old compared to his crewmates I guess and he had the codes agent Smith desired. What about Mr. Reagan, Mouse, Switch, Apoc and Mrs. Moss?
I guess Mr. Reagan has never been in Zion because he was unhappy outside the Matrix which probably wouldn't be the case if he lived in Zion. And perhaps Mouse was too young to visit the city as yet. But I think all the hoverships visit Zion once in a time.