Stu, if he tries to teleport on you, you can easily 3 shot him with faster unload. You only need one cube advantage so that he doesnt three shot you, which is pretty easy since Stus dps is higher so he can break more boxes faster.
Bibi has like 12k health at max level with shield and gagdet. You can just eat three shots and bait super, or just wait for storm to close in. Surge has low health so if he gets to storm closing, he always dies pretty quickly.
I guess Gale. Doesn't get 3 shot and can stun him with super.
No one really counters him once hes level 3/4. The trick is just to kill him before he levels up, any long range or fast brawler can kill him pretty easily when hes level 1/2. Brawlers like crow or max easily deal with a level 1 surge.