If Yamato has the mythical DF of Byakko then she stays on Wano as the new protector of Wano ,replacing Kaidou who is the Azure Dragon. Byakko is the guardian of the West while Azure Dragon is the one of the east.
It somewhat signifies the change that will occur in Wano after opening of the borders and the shift to the new era.
Very interesting observation. That would basically seal the deal if confirmed.
I remember there being a huge fuss over why Kaido's dragon form was blue considering how unfitting the colour scheme was for his character. With this added context to what we already know in the story, it's confirmed that's what Oda was going for.
I can very easily see Yamao's zoan being a white tiger based on her colour scheme:
We saw her fangs and she was growling this chapter too. When you take into consideration her role guarding Momo and her strength and sense of duty then it simply fits too well.
I already saw Yamao playing that role anyways, but with this insight it's now even more likely.