Whipper's have the ability to detect SWs. Yes it's a waist of skill points but, I find myself with enough left over that I spend in active buffs. No doubt that I would be able to have that skill pretty high up. Along with that WHs have the second highest damage in melee (second to the SW) add that on to the higher DEF and massive HP pool and I'd say she stands a very good chance. Yes the SW has skill locks and stuns but, WHs have skills of both quality and quantity.
In the end though, introduce a Clone ARC Trooper and that's one dead pair of Arkana. Hard maybe even toss in a Narak or a Makuta, or God knows what else. The point is the Arkana are sorta weak sauce compared to what I've seen.
A better question: Which will win in a fight Knights in shining white armor (Grand Army of Republic aka Clone Troopers) or sluts who are to busy fighting each other when they should be wondering how the **** are they gonna kill something that can squash the empire state building (Arkana)?