RWBY - MAY I JOIN?

Or it's possible that they'll be doing what most fighting games do and just dub it over with subtitles when it comes to a foreign language.

I mean, look at Tekken. A Spaniard, a Japanese Man and an American all walk into an arena…and understand each other!

Japanese learn English as part of their curriculum, so we know that Yu atleast understands a bit of what she's saying.