As with most if not all Yakuza games, Yakuza Kiwami also comes with its own share of unlockable costumes too.
These costumes are known as DLC but thankfully they are completely free which is usually custom with the series, thus far at least.
These can be unlocked after completing the story at least once, from there you need to select the Premium Adventure Mode.
When you are successfully in the Premium Adventure Mode, you will then need to either speak to Bob the Clown or head into Serena and more specifically the dresser there. You should hopefully see the different costumes there.
The below video is a showcase of all of the different available costumes within (YK) Yakuza Kiwami.
(NOTE: You CANNOT wear these costumes in story mode)
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