I play with a japanese player. But my japanese keyboard did not work, so i typed in english , and then my messages got translated to japanese! It might be a problem for english players to communicate, but for communicating with japanese players it seems helpful if u translate their messages. there are other places to chat for eng players. it may be fine, but it’s both good and bad.
Edit: there is an option to turn it off! In the chat menu, tap on 「翻訳開始しました」And in the pop up: click on 「決定」(it has the word “confirm” below.) hope it helps!