I think revan takes it. Why? I think anakin was still not as strong as yoda or sidious by this time, yet, i think that revan, even if he was slightly weaker then sidious (in my opinion), he would be much close.
Also, i would like to ask something: i saw people saying that tge ancient siths were all stronger then revan. This is not right, when Revan talked with Adjunta Pall in his grave, he clearly said revan was superior to him, he said several times that he was "so strong with the force" and all that kind of stuff, and you could be dark or lightside user, in both sides he say and he is admired about how strong revan was in the force. And he was 1 of the most powerfulls ancient siths... Also, even the great Darth Bane was terrified about Revan's force knowledge.
So, i say that we shouldn't underestimate Revan. I think he wins, with much effort probably, but i think he would win.