Dunno if its been mentioned at all or whether it exists(don't care really) but here it is from the horse's mouth as it were.
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The producer of the multi-million selling Yakuza franchise has let slip that a 3D iteration of the gangster brawler was created at some point.
Writing in a blog post following a visit to the Nintendo World event over the weekend, Sega’s Toshihiro Nagoshi teased, “Yakuza 3D was amazing,” before stating that he’d like to offer fans a gander at the project one day.
http://www.psu.com/Sega-created-3D-Yaku ... 391-p0.php