I tried to join Multiplayer.
Network Session -> Act as: Client, Entered host's global IP address correctly -> Go
"Select Session": only shows "Looking for sessions..."
We are in all discord server and confirmed any other members could join the session so it is not a host port forwarding problem.
I also set Windows Firewall to allow "F:\SB Pro PE\Release\SBProPE64cm.exe" to use both public and private network.
I only use Windows Defender and no other anti virus software.