Yes, this M.2 slot supports Thunderbolt 3.
Yes, this M.2 slot supports Thunderbolt 3.
Yes, you can purchase a PCI adapter to connect a Thunderbolt dock, allowing seamless switching between your laptop and main station.
It doesn’t seem to have a direct thunderbolt port on the back, and there’s no visible thunderbolt header either—something needed for ASUS Thunderbolt EX cards, for instance. It looks like you probably won’t be able to use thunderbolt features on this board. I haven’t checked all possible alternatives yet, so I might be mistaken.