Maybe some new info from here :https://www.factornews.com/article/e3-2017-premiers-empalages-cadeaux-dans-mount-and-blade-2-page-1-43229.html
sorry but i'm french so my english is not so good:
-They don't know yet if they want to limit the battle to 500 or 1000.
-The physics are not "prioritize" (I don't know the term in english but in other words, the game will run the same on nvidia and amd).
-The game will be CPU heavy (6 cores recommended but 8 cores would be the best).
-The game is not GPU heavy
-They are trying to integrate the coop but for the moment nothing is certain.
- 7 people are working on the engine and there are 70 people working on the game.
There are 3 levels of AI: a) one for the faction
b) a second one for the army
c) a third one for every NPC but the journalist has seen the AI doing weird things (no reacting,....)
-For now, they are not planning gamepad or console port.