Some propaganda of average would really really help as people has completely stupid takes on distributions and thus have unreasonable expectations by taking media/social media too seriously
Yakuza director explained it - in general roles given to attractive. And it take some courage and will to step out of standard trope "it hard to explain in narrative but we will put pretty chick anyway as she markets better".
Atsu is just average - you go out on the streets of big city and 70% of middle-aged women will be like her.
It's actually a good example of DEI (it's not a bad concept btw, it's just occupied by shitheads) - same as it is everywhere else - give some power (exposure) to common folks, not just to beautiful, smart, rich and powerful.
It's just a standard choice of pretty Asian. Not average SP trying to portrait.