Against Legends Grievous/Grievous depicted as the animal he should be, Maul takes sabers in a difficult bout; his connection to the Force would see him further than Grievous' processors and cybernetics. He absolutely punishes Grievous with the Force and possibly uses him for spare parts with Mechu-deru in round 2, and then in round 3 I imagine he would dismiss Grievous like in SoD or just pummel him with TK.
__________________ “The galaxy must experience the pain of death and the rapture of rebirth as I have. I will bring chaos. It is time for war.”
Grevious takes this first round solidly - non tcw/non jobbing. The Force wielder wins the Force round. And Maul can only hope to BFR the second, otherwise he certainly is dying.