1. It is possible to send Rcon query from Rust server to another server or I need to create custom Oxide Extension?
     
  2. What are you actually trying to do?
     
  3. I want to synchronize players count number between servers, then show it via GUI menu.
     
  4. You could do this with a MySQL database.
    Plugins don't have access to raw sockets iirc.
     
  5. If so, I will choose Oxide.Ext instead of MySQL.