Again, they've already been showing how these systems work in single player because they work exactly the same as how they do in multiplayer, except you're controlling each character, just as in D:OS 1 you can roleplay your two different characters antagonistically. Many find self-competition awkward, but if you're willing to roleplay multiple competing characters, you'll have basically the same experience as a multiplayer game (naturally, you'll only be able to control one character at a time, so perhaps some encounters requiring more or less simultaneous action will be impossible in single player, but I'm not sure if those will exist.)

In a direct confrontation, your characters will surely become hostile to each other just as in multiplayer, and I'm sure you'll be able to set up contracts between characters just as in multiplayer (though it's still unclear how this will work exactly.) Larian's ethos seems to be that single player and multiplayer experiences should complement each other, where design for multiplayer naturally creates a robust single player experience, so I wouldn't worry too much about them neglecting single player, even if they have been emphasizing multiplayer a lot.

Bard Mod for D:OS2