User blog comment:Jkphantom9/RWBY Japanese fandub release date!/@comment-11942246-20140410080348/@comment-4010415-20140410232111

There was definitely another RWBY video that had Japanese voice acting, but apparently, it was done by people whose second language is Japanese or something. Someone said they're glad that one of the people in that other one isn't involved in this one because her accent when speaking in Japanese was bad.

So, I'm pretty sure I'm not thinking of the Chinese dubbed one.