Modifying the code for an upwell structure could probably allow for what the OP is asking for. IMO, this would be more useful for carting around jump clones though, which could be carried in any ship since it would merely be a game object / asset.
As for moving npc passengers around, it would be fine to treat them like the commodity market in the current setting. Or add specific distribution missions (assuming they don’t already exist) that have the player ferrying passengers.
However if you want a more in depth passenger system like I mention in the 3rd section of this post ,which details a system for crew and officers for our ships, then I suggest taking a look at the linked topic.