I've searched and couldn't find anything like this. So what I am searching for is when a player for example writes in chat !forum or /forum a MOTD opens with Forum site. Or anything else. For example if player writes !donate or /donate a MOTD opens with Donation site.
Is there a plugin for it? I've checked this one ( https://forums.alliedmods.net/showthread.php?t=221576
) - but this one is only for admins.