Here's how I see the fight going.
Whitebeard starts out with a Gura shockwave, which Sanji responds by using Sky Walk upward to avoid it. Sanji the charges down towards Whitebeard with a Diable Jambe Concassé, which Whitebeard blocks with his Naginata.
The eminating heat from the Diable Jambe slightly bothers Whitebeard, which prompts him to use a Gura infused punch like he did to Oden, which knocks Sanji away.
Sanji breaks a few bones, but quickly regenerate with his Germa abilities. Sanji then decides to turn it up a bit, using his Super Speed. Sanji disappears from Whitebeard's eyes, but he barely manages to block a Coiler kick to the neck thanks to Kenbun. Whitebeard tries to counter again, but Sanji dodges, using
Cuisseu Crusher, following up with Party Table Kick Course, knocking Whitebeard away.
Trying to regain his footing, Whitebeard plunges his Naginata into the ground to stop himself from being sent too far. He looks up to see... nothing?
Sanji appears behind Whitebeard,
kicking him in the back, but Whitebeard takes this and uses it to his advantage, grabbing his head and crushing Sanji's skull with a Gura infused strike.
Keeping him on the ground, Whitebeard uses his other fist, infused in Haōshoku to strike Sanji, but instantly got burned before being able to strike.
Sanji pulls out Ifrit Jambe.
Sanji is now truly invisible, zipping around the Mirro-World, landing fatal strikes to Whitebeard and retreating before he can counter. Whitebeard mangages to block a couple strikes with Busō Emission, but the sheer amount of attacks coming toward him eventually overwhelm him.
Sanji wins.
