Great! Just updated the first post.

Not sure I understand the question though. I don't speak Japanese. The process of visiting an onsen (once you've learned what behaviour is/isn't expected of you, just as it's outlined in the link you posted) is very straightforward.

Perhaps one of the larger onsen, like the Oedo Onsen Monogatari in Odaiba, would be the place to head for if language is a concern. I personally tend to prefer the older, more modest, neighbourhood onsen as the regulars are often more of a highlight than the waters and baths are. It's a real shame the Koshino yu is no longer in business, the lady who oversaw the bathing areas spoke exquisite English.