The PSP exclusive Yakuza: Black Panther (also Black Panther: Yakuza New Chapter) or as its known in Japan Kurohyou: Ryu ga Gotoku Shinshou came out way back in September 2010. The franchise got a sequel and even a TV show based on the new, younger leading character. Sadly due to low software sales in the west we never got a localization of this spin-off franchise. There has always been a really good online guide you can use but now you can play it with a fan made patch.
CD Romance patched English ISO
How complete is the patch? Well, its only translated the main story from start to end, but substories haven’t been translated yet. At least this is the feedback I’ve gotten which has made me personally made me want to wait for the full project to be translated. You can check the translation team’s GBA Temp thread.
For those of you that have been waiting for these games to be translated, you can thank: Aegehn, Fshadow, KHHSubs, and FlyingClimber for putting years of hard work getting this released!