Ok? Shazam nullifies every interactable with his own teleport and has a wake-up.
Scorp can kill you with the pig in arkham? So can anyone, only difference is shazam has the means to say "nerp" to it all.
Scorp vortex is irrelevant to Shazam, actually its irrelevant to anyone with a half decent d.2, armor... Wake-up...
Shazam has a "Guess wrong and you are eating 30-45% on the cheap with a scenario reset." Scorpion has a "If you guess wrong, you'll eat 20% (until I run out of meter in 2 moves).". Most of the cast can control interactables through means of armor, immunity, or projectiles as it is, so scorpion isn't very special. Batgirl does his job better, so as far as "viability" goes, his is sitting at a prime 0. He is a poor man's Barbara. Outdone by a crippled woman, how sad.
His vortex is weak, his damage is weak, his projectiles are weak, he has nothing that makes him any more of a choice than Batgirl.
Everyone on the list has something available to them that no other character can do quite as well. Scorpion doesn't, even moreso with the new MMH release.
His existance as a anti-zoning character is done better by 2 other characters, his damage is awful, and his niche of "you can't use interactables" is done by plenty of other characters who don't suffer from a lack of EVERYTHING.