How do I set up a custom game
Call of Duty: Black Ops 4 is available.
We’re suggest you’re following an instruction at Unsupported Games
It’ll work if you put the destination’s public IP address proper way but
I doubt are COD and MW open to public their server’s IP address as in
general situation.
But sometimes, some people are getting those information anyhow so they
can make their own Custom Item in that case. So if you get those
information in somewhere then you can try it yourself.
Or try to inspect network packet by yourself like with
Wireshark.
But it’s not an easy work.