I was fooling around with IC's and got ***** by a a Zelda.
I think that ICs still have a very slight advantage, just because they are tiers above Zelda, and have more options, but Zelda can play that MU, I think. Kicks/fsmash separate them really well, she can kill Nana in mere moments... The thing is, Zelda kinda needs to be in the air for kicks, and IC's can WD under her > utilt/usmash if she gets too comfy in the air. They also have powerful moves that can kill her early.
Maybe 55:45 in ICs favor? I simply don't believe that Zelda wins, or that it's even.