Revan and Luke are basically equal with Revan being a little stronger, as in 999 out of one thousand times they would draw and the one time Revan would win type stronger.
Malak and mace is hard to say, Malak has more experience more force powers and extremely long limbs with a long saber, but mace had a style that was good against darkside users, I'm still going with malak.
Now that being said what if Revan fought mace and malak fought luke, malak could hold off Luke long enough for Revan to finish off mace, Remember next to Revan malak was the most powerful force user in the galaxy, he had knowledge from some of the same sources of Revan maybe not as much but still that's a lot of knowledge.
Now all that being said we come down to one last factor, chemistry malak and Revan fought side by side for years they were the best of friends and did everything together so they fought together very well opposed to mace and luke who didn't know each other and would have trouble working together.
In the end sith win.
P.S when does malak beat kavar emperor Revan?