How exactly do Smuggler's Ports work? I've converted to Council of Esus and enacted the resolution but nothing seems to have happened. The option to build them hasn't appeared, and they don't seem to have appeared in my coastal cities automatically, either.

I don't think they have been implemented yet....

A unit builds them in a coastal city, not the city itself is what I think I've heard.

I've gotten smugglers ports trough worldbuilder, but never without cheating. I've never seen a way to get them without cheating, and I've had the vote for them pas quite often.

Same here. Voted yes, it passed, but never saw an option to make them.

I just noticed its cost is -1, which means it can never be built. Maybe someone from the team can tell us what the intended mechanism is?

looking at the code you can not build them as they have an <icost> of -1