A while back, we tweaked the terminology on the wiki.
This was to make things easier for people to find, as well as to be as accurate as possible, and - while some name changes like "General Devil" have been debated - the changes to group names seems to have been positively received. We have thus changed phrases like "Seigi Chojin" to "Justice Chojin" in articles.
Generally speaking, this has made things a lot easier on people. The words are easier to spell and search, for non-Japanese speakers, and it's also clearer what is meant to non-Japanese speakers, too. It's been helpful all around.
Unfortunately, categories have - until now - remained the same.
Our goal is to change these categories over time; sadly, the bot to rename en masse is . . . difficult. It has been deleted pages that have redirects, which means we're going to attempt to do this manually instead. We're going to start with the recently edited "Seven Akuma Chojin" and "Six Devil Chojin", as - as the name suggests - they only have seven and six articles apiece.
The larger categories, such as "Seigi Chojin", could take a lot longer.
Please bear with us, and feel free to delete the old categories and replace them with the new categories, if you're already editing an article anyway :) We'll try to get this change done as soon as possible, to make it easier for everyone!
Tl;Dr - We'll be changing categories with Japanese names into English names over time; "Akuma" to "Devil", "Seigi" to "Justice", "Zangyaku" to "Brutal" etc.