The CX-9 is a new option that arrives to Modern Warfare, and as consequence, to Warzone as well.
If you were looking for a new SMG, the CX-9 first showed up in December 2020, and never made the official appearance for Warzone and multiplayer modes until now.
It comes with a decent fire rate with a fairly easily recoil to manage. With the right attachments, however, reload time can be minimized drastically, making it a consistent and speedy option to consider in your setups.