I’m really not familiar with Japanese product and even less familiar with the 1st edition print run that started soon around when Nintendo stopped that print run on the English side.
Do we know anything about the print run numbers for sets like Wind from the Sea? Does the 1st print run fetch a premium or is it not really recognized by collectors on the Japanese side?
Actually, for Japanese sets unlimited editions are overall harder to come by, rarer and more expensive. There are exceptions of course, but for most Japanese sets that have both a 1st and unlimited edition print run, UED is harder to find.
Although I’m not too familiar with the Japanese Aquapolis set you’ve mentioned, I’m pretty sure UED is rarer for that set in comparison to 1st edition as well. It’s definitely the case for Skyridge (the set after it), and Expedition Base Set (the set before) is kinda a special case where the UED were only handed out as promos or special event cards (see this article) and are probably the rarest UED Japanese cards that are out there (although L2/L3/Champions Pack cards are also pretty damn hard to find in UED).