Creative Assembly is bringiong out the big guns by revealing a fully revamped diplomacy system with never before seen levels of detail. This is an extremely promising step forwards as we see new features and returning old ones such as region trading. Check out the blog post here: https://www.totalwar.com/blog/diplomacy-in-total-war-three-kingdoms-part-1
Check out Legend's video: https://www.youtube.com/watch?v=UtFZUSPLRrA