Zelda is not overpowered, especially since her ranged Dash Attack and ranged D-Tilt moves were Nerfed.
She only seems OP at first to people who can't adapt to playing against her. If you don't learn where her ranged hitboxes are, or you don't shield and dodge often, you're going to have a hard time against Zelda.
Try shielding her ranged hitboxes and grab her when she warps to you, and edgehog her if she goes offstage. Beware D-Air though.
Don't let Zelda keep you at range. Go after her and stay close, and her options become very limited.
Zelda used to be "A" Tier, but the Nerfs brought her down to "B" Tier... If anything, Zelda's ranged Dash Attack and ranged D-Tilt should be Buffed (or at least tweaked) a bit. Ranged D-Tilt in particular needs help.