Back at ya with a sub class setup. The AK74u is pretty OP in cold war so I would expect the same in Warzone. Here is a class setup to try. I still don't think it's as good as the mac-10 but it's almost there.

Attachments for the AK74u:

Stock: Spetsnaz PKM Stock
Muzzle: Gru Suppressor
Barrel: 10.3" Task Force
Ammunition: Spetsnaz 50 Rnd Drum
Rear Grip: Gru Elastic Wrap

Like I said before, not as good as the mac-10 but still worth giving it a shot. Try it in cold war as well! I'm sure it works great in regular multiplayer as well.