At this point, Yakuza releases in the west have become far more of a sure thing than they were there for a while, when it was a crapshoot whether or not a new Yakuza game would ever come over (a few of them such as Yakuza Ishin and Kurohyō: Ryū ga Gotoku Shinshō didn’t). Yakuza 0 launched earlier this year, Yakuza Kiwami just now, and Yakuza 6 is due out next year.
But there are more Yakuza games on the horizon, of course- there is Yakuza Kiwami 2, the remake of the second game in the series, Yakuza Online, the PC and mobile online game based on the franchise. And while it is not a Yakuza game, the same developers’ Fist of the North Star has also been announced.
Sega has recently sent out a survey asking players about potential localizations for these games. You can take the survey here if you want to ensure the series continues to get localizations.