Hi pawlisko.
See my post here, http://forum.mikrotik.com/t/mikrotik-wireguard-server-with-road-warrior-clients/148392/1
Why you ask, because in my iteration on an earlier version for of ROS7Beta , even though I could, I did NOT use IP addresses for my WG interfaces.
Therefore it can be done. The biggest difference is that dynamically the router does not then create the necessary IP routes for the interface and it has to be done manually.
We should be able to get you up and running!!