Siral_Exan said:
It's not worth a report, IMO, because there are more problems to solve than one user adding a bunch of tags. The problem is that they claimed the names are official, and if they are right we may want to use those names instead. Since I don't know which names are official and which ones we'd prefer, and I can't say for certain that they are breaking the rules, I'd rather have someone who knows the right terms make an alias request instead of reporting one user.

Fair enough. From your wording I assumed they were intensely/aggressively and repeatedly tagging after their removal, but if not then yeah maybe not worth a report. But that is up to you, I consider it tag vandalism myself.

From datamining, aka ripping the data and names straight from the official source, the Japanese original names shown on the spreadsheet should be correct. Romanizations of pokemon names (they're not romanized ingame, but from outside sources like merchandise) sometimes can be a bit iffy, as it can depend on the type of romanization used. Most commonly people use the Hepburn variety when romanizing, so usually it isn't a problem.