I kind of don't like Romaji.

For me it's a matter of convenience. Writing "other world" takes too long than to write "isekai". On the other hand, I won't write "Mobile Suit Gundam" as "Kidou Senshi Gandamu".[ I guess I just write whichever my brain thinks is easier.

And in case you don't know, the Romaji used by us foreigners is different than what Japanese people use. An example is when writing "tsu" we usually write it "tsu" but Japanese write it "tu".

If you're immersed in anime culture there are certain Japanese words that you will just know. And if you don't, you'll learn them quickly enough due to the frequency of their use. Words like isekai, tsundere, chuunibyou, otaku etc. No need to approximate an English translation for these terms.

As for Sailor Senshi, since it is a phrase that is so deeply integral to the work and is used probably every episode, it is fine to leave it like that and the audience should be able to easily surmise its meaning. If you had some random anime that used the term "senshi" one time in one episode, then in that case it would be appropriate to use an English word for translation.

@FanofAction Nisekoi is also a funny case since its sometimes titled as "Nisekoi: False Love" when "Nisekoi" literally means false love, so it's technically being called False Love: False Love. I know for sure nobody will ever call it False Love. Also, I tried typing False Love in the search bar on MyAnimeList, and the first search result actually is the first season of the anime.

I don't mind when they add those subtitles, because it give non-Japanese-speakers a subtitle they can understand but keeps the real name of the show intact. The fewer dub titles I have to remember, the better!

And speaking of Romaji, I always hated how the localizers spelled "Wotakoi" in English. It's academically correct, but they should have known that English speakers would pronounce the silent W like「ウォタコイ」. Would have been way better to just write "Otakoi" like it's pronounced. Same reason the Genki textbook writes XはYです as "X wa Y desu" for new Japanese learners.)

I think it's fine to use romaji words in a Japanese context. It helps set the vibe of the text to show the reader that we're talking about these things as they apply to a Japanese setting. "Isekai" is a pretty specific idea and translating it to just "other world" actually makes it more distant because people have to realize that by other world you actually mean isekai. It makes it take that much longer to read. Calling it "portal fantasy" would also be confusing. These might describe the genre, but if people are used to calling it isekai trying to Westernize it doesn't make sense.

I have the same gripe with translating senpai/kouhai to upperclassman/underclassman. Those words seem to only be used in the context of translating the Japanese words, as if someone just found some obscure equivalents to Japanese concepts, but then you have to look them up and realize they just mean senpai and kouhai. Douki is also a word in that same category which means "someone who got hired at the same time as you". "Peer" might be close, but it's better just to leave it as douki because it's less ambiguous.

Obviously you can go too far with using Japanese words, but if it's already accepted to use the Japanese word or if there isn't a good English translation then going out of your way to confuse people by coming up with English analogues is just going to make your writing worse and harder to read. You've basically become more pretentious by trying to avoid Japanese words. I hope you don't call sushi "fish rolls" and tsunamis "danger waves".

@Lucifrost Tidal waves and tsunamis are different things.

@Jim69
How did "Syaoran" become the most common way to spell the name of Cardcaptor Sakura's love interest? Another case of Wotakoi, especially cringeworthy since the character in question is not even Japanese!
https://myanimelist.net/character/3029/Shaoran_Li

I think it's fine to use romaji words in a Japanese context. It helps set the vibe of the text to show the reader that we're talking about these things as they apply to a Japanese setting. "Isekai" is a pretty specific idea and translating it to just "other world" actually makes it more distant because people have to realize that by other world you actually mean isekai. It makes it take that much longer to read. Calling it "portal fantasy" would also be confusing. These might describe the genre, but if people are used to calling it isekai trying to Westernize it doesn't make sense.

I have the same gripe with translating senpai/kouhai to upperclassman/underclassman. Those words seem to only be used in the context of translating the Japanese words, as if someone just found some obscure equivalents to Japanese concepts, but then you have to look them up and realize they just mean senpai and kouhai. Douki is also a word in that same category which means "someone who got hired at the same time as you". "Peer" might be close, but it's better just to leave it as douki because it's less ambiguous.

Obviously you can go too far with using Japanese words, but if it's already accepted to use the Japanese word or if there isn't a good English translation then going out of your way to confuse people by coming up with English analogues is just going to make your writing worse and harder to read. You've basically become more pretentious by trying to avoid Japanese words. I hope you don't call sushi "fish rolls" and tsunamis "danger waves".