The original games (BG I & II) did this too but at least I could make a solo multiplayer play through and skip all the tedious infighting and power plays of the plot characters,
BG3 still allows for it, but it's rather tedious. You need to launch 4 seperate instances of BG3, host game with one, and join in with the others. Create your characters, start the game, make a save, quite with three accounts - and vualá! You have 4 customs. If you create party that way, you won't be able to dismiss your party members as they are all player characters.
