Traya wins she trianed revan so she knows all he is capable of also she trained Nilihus and sion and so forth so she knows what each is capable of and can probably do most things they can
Nihilus was a wound in the Force. Traya is not. She can't do what he can. Also, Traya/Kreia was only One
of Revan's teachers. Revan had more than half a dozen Teachers among the Jedi and learned from all of them. And then he went to war and tempered his skills with experience in combat. Revan knew and understood war better than anyone else. Also, Revan expanded his knowledge during the war and this was evidenced in KotoR. He was already learning of the Rakata and the Star Force prior to the Emperor turning him. This was revealed during the vision on Dantooine.