Have you heard of the news about Don’t Starve? It’s going to have multiplayer mode soon. However they deleted and blocked posts about multiplayer in their forums all the time because they said back then it wouldn’t make sense in the current state of development to think about multiplayer if the goal is to create a unique singleplayer experience.
So basically this is how Warhorse might approach it, too. Dan said multiplayer mode might not be a feature in Act 1, maybe it could be implemented in Act 2, but that’s more of a speculation rather than reality. Until then one or another person might have created a Multiplayer Mod. The best option by now is to wait for more input from the devs about this topic rather than creating the illusion of multiplayer possibility via an extra category while this feature is not stated as official feature.