Wait Ace went to Onigashima ?
Yamato was roaming around Wano before hitting the age of 8 so she found oden journal before that age.
But if she was trapped in Onigashima....how was she present in Oden execution?
This is a mess.
Yamato was 8 years old when she witnessing Oden's execution.
And then she watch her father (Kaido) killed Oden which is her idol.
And then after the execution, someway somehow she found Oden's Journal in Kuri.
After that, she trying to hide that Journal and because she is still a child, she casually talk to Kaido that she want to be like Oden.
Kaido knowing this, he went back to Onigashima with her and put a handcuffs on her for 20 years. And now she is 28 y/o.
Yamato said he meets Ace, and she had her handcuffs.
Thats mean Ace was in Wano and visited Onigashima.
And i can see her handcuffs is fake, thats mean if She leave Onigashima her handcuffs will not explode at all.