Please read again my post.
For hosting via DirectPlay you need external IP. (Almost all the time minimum 1-2 players from my community have it.)
Other way for organize MP session is Tunngle (you don't need external IP) but it is "third" program for showing you commercials. Also i had 2 times serious problems with uninstallation Tunngle.
Other "virtual LAN/ext IP" programs like Hamachi, Evolve often causes problems with connections (especially Hamachi). Some peoples have it - some others not.
We decide to play without "third" programs because it is easiest way for checking internet connection settings.
Discord is only for communication:
- voice channels during game
- chat before/after game
It is useful to arrange a meeting because DW players are from different Time Zones.