Lobo (hard to get close, crappy trait) Hawkgirl (no range on normals, long windup on specials) Bane (weak grappler, trait gets him killed) Joker (long windup on specials, crap trait) Shazam (hard to get close, long windup on specials)
These are the worst IMO. Most of them have solid damage once you confirm, but it's getting that confirm that's a problem. Bane's issue is he needs to use his trait to be good, but once his trait runs out he's terrible.
Special mention for Flash, who's actually pretty solid locally but SUCKS online. Needs some more leeway for his combos, they're too tight and drop easily with any lag.
The big brain am winning again! I am the greetest! Now I am leaving Earth for no raisin!