While charming, Sakura Note is neck deep in Japanese culture and customs. Audio Games, the developer, notes this on their company blog. But, hey that doesn’t mean Sakura Note will be stuck in Japan. (Thanks for the tip Nominal!!)
Audio Games also says if there is potential for business they will localize it. They even (sort of) translated the text into English, a bold and uncommon way to appeal to early fans.
Now for the potential business part… Marvelous is aggressive when it comes to releasing their games, even niche ones, outside of Japan. I’d count on Sakura Note coming over. The question is really who is going to do the localization work.