A work in progress mod called Age of Bannerlords is ambitious, to say the least, turning Mount & Blade 2: Bannerlord into a full-featured RTS complete with base building, unit production, and resource gathering. At the same time, it retains Bannerlord's bones, so you can jump into combat at the ground level and control your units in a third-person melee.
Modder Bloc has been working on the mod on and off in their free team, and the building models are by modder modeleers FoozleMcDoozle and Errayn. “All the buildings are created by these two talented lads,” said Bloc.
There are some other fancy features in the mod as well, like dynamic marketplace prices, and progression through eras ala the Age Of games. A lot of Bloc's work seems to have gone into AI, teaching the enemy to build its settlements organically, form raiding parties of units, and scout out your base with light horse.
The units, of course, are precisely the standard ones you'll find in Mount & Blade's campaign. As are the factions—which is kind of nice. There's a built-in theme and balancing already there for Bloc to work off of.
You can find more videos on Bloc's YouTube, plus you can probably subscribe over there to keep an eye on the mod for when it actually releases.