Fear not, just about every character who isn't a zoner has a way to deal with zoners. Here are a bunch of examples...
Flash - Phase through projectiles and slow down time to get in.
Superman - Airdash to punish whiffed zoning attempts for full combo. Also air eye laser will probably be great for return fire.
Catwoman - Dodging projectiles with her command dodge gives her cat scratches, which powers her up. If you zone her carelessly when she gets in she's going to lay a hurting on you with the 5 point combo ender. Careless zoning only makes her stronger.
Wonder Woman - Bracelet parries projectiles, can airdash to punish whiffed zoning attempts for full combo.
Grundy - Armor and swamp hands. If you trade with swamp hands, Grundy might get hit by a projectile but you're caught and he'll probably get a combo. Plus armor.
Doomsday - Armor, teleport, angled shoulderdash that, when meterburned, can punish.
Aquaman - Projectile shield.
Etc, etc.
I missed a ton of stuff and I could elaborate on a lot more, but my point is, don't stress out. It seems like most characters have at least a few viable tools to keep zoning from becoming too overwhelming. Everything is looking good so far.