I've searched multiple websites for the JP version of this game (both for the physical copy of it and and the rom), with no luck. Could only find the USA/EU versions. Any tips on where to get it?

So I'm not sure why this is the case, but the current 100% definition involves beating the game TWICE, once on normal and getting all diamonds, then again on EX. This seems ridiculous to me, and I think the lack of any runs on that category at all shows this.

I think that the 100% category should just be completing normal mode while collecting all diamonds.