While it would be kind of cool to see the switch playout it really doesn't make sense. How do you explain that Oden was very clearly still Oden while in the oil? When would BM have done this switch when she wasn't at Wano before?
More likely is Yamato is a fan of Oden's that's why he's wearing the same style rope thing(not sure what it's called)
More likely is Yamato is a fan of Oden's that's why he's wearing the same style rope thing(not sure what it's called)