Yes, it's included and works perfectly for me. It's also easy to attach and adjust thanks to the magnet.
However, I have now laid a flat LAN cable through the flat because I also had to move the NAS to the office.
My personal experience with Devolo and Power over Lan has not been good, especially in terms of speed. + Power consumption: These things are always hot. I only have a few in operation because there's absolutely no other way.

yes is included. but i recommend going with power over lan. devolo or tp link. is more stable, better ping and faster.