I'm aware that the always-online functionality of Modern Warfare 2019 and/or some type of built-in anticheat (or something along those lines, at least) prevented the creation of a trainer for the game.
Is it known if that's the case here as well, or will a trainer be coming?
There is a single-player campaign so probably yes. We'll see soon.
Can you hack anything like health or ammo using CoSMOS on the campaign or is it stored on the server?
Haven't checked yet, and I admit to not being familiar with CoSMOS, but I'll check it out and report back