Im sure its to late to add a new weapon but i just had an idea i wanted to share anyway.
I know you cant dual wield but what if you pick up an smg it comes as a pair?
If you see it on the ground its actually a pair and you dont have an option to ony use one.
Theres alot of reasons why it couldnt work (animation for throwing grenades), but i just wanted to share that idea.