Given the ROTS novel and script have Anakin getting stronger as fight goes on, and given even Dooku drop kicked Anakin earlyish in the fight, then I'm guessing Sidious would take Anakin out quite early in the fight.
Even late in the fight I honestly don't see anything stopping Sidious force slamming or choking Anakin the way he's done to Maul and Dooku.
So outside of a Oneness moment where he can dominate the Son and Daughter, Sidious stomps despite Skywalker's massive amount of Saber skill and raw furnace heart power.