It appears that the first multiplayer mod for Kingdom Come Deliverance is currently under development. While we don’t know whether its team will be able to finish and release it, it did share a video showing a prototype version of player synchronization.
Do note that Kingdom Come Deliverance does not offer any modding tools at the moment. Back in May 2018, Warhorse Studios revealed that it will add mod support in 2019, though it remains to be seen whether this will be too little too late.
There is also no guarantee that the modders will be able to complete this mod. It would be cool, no doubt about that, however it will take a lot of effort in order to offer proper multiplayer functionalities in a single-player game such as Kingdom Come Deliverance.
But anyway, at least the following video is cool so be sure to watch it if you are one of the game’s fans that desperately want a multiplayer mode.