How to open Client window dynamically

When I want to run my game in multiplayer I have to set up number of players in Multiplayer Options to 2. A window for Server and second window for Client are then created at startup. Is there a way to create Client window dynamically from Blueprint (when ‘X’ is pressed, new client should be created), not at startup? I do not want to start new instance of the game as a Client and then join the Server session. It is hard to debug my game this way.

108073-num_players.png

Still looking for that in 4.20