also it's funny how many plot twists in the Yakuza series come down to no one having noticed that another character wasn't actually Japanese, just Asian
I guess it does underline how much of "looking Japanese" isn't actually genetic but fashion, hairstyle, behavior – all the subtle things that allow you to go to Seattle and distinguish between Japanese and Japanese-Americans on the street
"Japan's relationship with neighboring countries" has been a recurring theme (bringing in exotic organized crime rivals), often doubling with fellow recurring theme "neglected out-groups of Japan".
The introduction of Little Asia, the African touts in Kabukicho standin "Kamurocho" by 6, Zero showing foreigners have always been there (and calling back to the legacy of Japan's colonial involvement on the mainland)
This one there's a bit about the unimportance of blood as a climactic moment, which makes it sort of a climactic theme to the series. But for all that, even the friendly crypto-Japanese reveals have this weird undercurrent of They're Always Infiltrating, More and More
Honestly appreciate how Yakuza 7 plays with this, one of your party members is a barmaid applying as a hostess club as a way to get in, they’re like “but this club is Chinese women for Chinese men” and she’s like “that’s ok I’m a Japanese citizen but both my parents are ancestrally from China” and when the rest of the party has a chance to ask “really?” she’s like “pfff”