But she could change somehow after joining the crew like Robin did.
The issue with that is that Robin was both a surprise crew member and was clearly set up with a lot of question marks around her character that weren't really tied to Alabasta (Void century, will of D, her bounty, etc).
Yamato on the other hand is pretty much just tied to Wano specific plot points(Oden, her frequent interactions with Momo, her devil fruit, and Kaido's speech to her being about how the people of Wano will never accept her) and yet she has barely even had a character arc here. I don't really see where any development will come for her if it didn't happen here.