Suggested by iKnowledge Darth Plagueis is pretty impressive in the lore. He was the boss of Palpatine after all so he was clearly high ranked. That said, we never really got to see any physical abilities from him. His whole deal was more about predicting the future and mental feats. While good, that won’t be enough for him to defeat a true combatant like Bastila Shan. She can use various Force abilities like Lightning and additionally she was also very skilled with a Lightsaber. She would dispatch him in short order. Bastila Shan wins.
I still wouldn’t underestimate Plagueis. Even if he lost to his own pupil, it takes power to make Naboo have their coldest winter in thousands of years by merely being on it. He was also probably no slouch at fighting, due to him being from the future of Star Wars.
Yeah, I agree that he’s got to be really powerful. If we ever get a comic or a movie where we get to see him fully engage in some kind of big battle then I could see this changing right away. Not to take away from Bastila though. Bastila also seems very skilled