It may not be intended, but you can do exactly what you want.
Run the game twice.
Interesting. Running two instances of the game doesn't sound very healthy for my system, but might be worth investigating. Does it seem bizarre to anyone else that the devs would force players to go the long way around like this instead of just including the option in the actual game? (When they
already have the option in developer mode?)
Combat is turn-based anyway, isn't it? No one here has a mechanical problem playing multiple characters.
but out of combat you have to do everything sequentially.
sure, it might be possible from a mechanical point of view. but it seems rather awkward from a gameplays standpoint
Awkward? It's not that bad. Switching between different characters is pretty much second nature to me. Adventure Construction Set, Wasteland 1, Jagged Alliance 2, Icewind Dale, Temple of Elemental Evil ... there are tons of games where you can change viewpoint between several characters.
To be clear, I'm not talking about playing a wargame with four characters who are out to kill each other every moment; I'm talking about playing four characters with different motivations who sometimes work against each other. I want my elf character to be able to choose the "enslave the dwarves" dialogue option and my dwarf to "free the dwarves" and see what happens and maybe they end up fighting each other. Maybe one of them gets the opportunity to poison or steal from another and so I make them do it. This is very simple gameplay, nothing complicated or difficult about it.