Would be super hype if Sanji awakenes something that actually gives him a transformation, but solely for fights, similiar to Zarbon in DBZ, where he does not want to be seen by Robin or Nami while in it, because of some outrageous exoskeleton mutation.
Basically Vinsmoke shit on activation
Headcanon much, but fuck it lol
Btw nearly confirmed now, that Sanji is indeed modified and Sora's medicine just surpressed those genes. RS gonna trigger that shit