I wish I knew the origin story for that xd, it might have even been found on accident. I know that the yakuza 0 arcade skip was found entirely by accident, where froob decided to go the arcade one run and realised that he didn't have to wait as long.
GOOD VIDEO very interesting and informative, do you know of any more out of bounds exploits in the yakuza games such as the one you mentioned with akiyama in y5? feels like there's hardly any to be found in the games
The yakuza 5 out of bounds is the only one that is useful for speedruns. The original yakuza 1 for the PS2 has an out of bounds skip, but as far as I know there hasn't been anything useful in terms of the speedrun. Here's a link to it if you want to check it out: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-FPQj5xaATaw.html