Darth Traya has her lightsaber floating thing which is bad for plagueis since he is a larger opponent
DeviantDefiance
Traya, definitely outclasses Plagueis
MythLord
Plagueis one-shots her.
Trocity
I don't think plagueis can compete with trayas 3 lightsabers at once, and she could also just kill him with her drain ability. Plagueis has more than one heart but that will only delay the inevitable.