What type of Nen can improve the user's flexibility the most: Enhancement or Transmutation?

I was wondering because an Enhancement type Nen user can amplify or enhance the flexibility of their body, but theoretically a Transmutation type Nen user could transform their aura into a malleable internal layer that would cover their muscles and bones to be able to crush or contract their body to impossible levels without breaking, which would allow them (hypothetically) to slide through cracks, crevices, holes a few centimeters wide and be able to stretch and bend their joints without hurting themselves, but all of that is a hypothetical possibility.



My question is, what is the best type of Nen to create an ability that allows the user to stretch in an inhuman way (Like Nyan from One Punch Man or Edgeshot from Bnha)