It doesnt matter in other canon can be established what ever. They can change it in this show, wich is even more canon then the other one.
From the other episodes though i dont recall Ashoka getting the uper hand in lightsaber dueling skills at least. However again it doesnt matter if Ashoka could out duel barris before. That was then this is now. That is the nature of star wars and of storytelling drama.
It would make little sense, there is no way Barriss could master dual wielding in short time and Force Choke people from so far.