Lmao, HxH really lives rent free in your head, right?
HxH worldbuilding is nothing to talk about for a work of fiction but it's correctly done, even if super lazy when it comes to its fucking lame worldmap.
It has credible geopolitical conflicts, political intrigues, a real structure of the underworld with internal power struggles and mafia families, unknown and unexplored territories with the setting not shying away from exploring notions of colonization, expansion and plunder by the developed countries... As I said, nothing to talk about in the world of works of fictions, it's just ok (although it's unironically above most mangas because for some reasons, most mangakas simply don't give a shit about even basic worldbuilding, so just doing ok worldbuilding already put you above most of them).
On the other hand, OP has jam islands inhabited by broccoli-men. Every single island is "a kingdom in the hands of an evil guy who has overthrown the rightful ruler, and there is a princess in distress". There is not a single society in the One Piece world that is developed and explored in depth, no credible notion of geopolitics, inconsistencies in abundance (a single faction that controls the entire world, composed of extremely distant islands that never communicate with each other). OP worldbuilding is actually one of the worst in any manga I've read. It's lazy and immature.