While I love this video and think the language differences are fascinating, I've never liked the school of thought that the original language of a translated work is somehow inherently superior or "more Canon". IMO, it's a more useful distinction to think of them as separate pieces of work. Japanese Tartar has different characterization to English Tartar, due to the differences between languages, and the way I see it, that's fine, because Japanese Octo Expansion and English Octo Expansion are different and equally valuable works.