Do you have to pay for changing your leader? Because there is no option for changing the leader, I always have to play using Captain Cutter. So probably there is a DLC to make it possible to change the playable leader?
You can change your leader in every game mode besides campaign. And no you don’t have to get dlc for it. Halo Wars 2 gameplay: multiplayer deathmatch 1v1 - YouTube . This would be the leader selection screen you get if you start a game mode.