My guess would be that they make it like Pillars of Eternity.
There is one char and this is your story. You will find companions with their own personality and goals, but you can create the entire group if you like.
In D:OS1 you found 4 companions and each one had a personality and a quest. But you could als buy henchman if you like.
The question will be if you can create all chars at the beginning or if you create one char and you can hire others later (like in D:OS1 or PoE)
In multiplayer, everybody creates his own char. Their backgrounds and goals are hidden from each other because each player creates his char seperately. ( Well, the hiding gets difficult with a split screen.)

Prof. Dr. Dr. Mad S. Tist

World leading expert of artificial stupidity.
Because there are too many people who work on artificial intelligence already