Why do you need a repeater. If you plug your pc into the remote unit with ethernet you have in effect made a wifi adapter. It is not much different than if you had bought a wifi USB adapter. The speed between the remote unit and the main router will be about the same as any other wifi connection.....much much less than 1gb ethernet.
There are some repeaters that can run without WDS. I think tplink can and they call this "universal" repeater if I remember correctly. The repeater acts as a router with a wifi WAN connection. This means you will have issues sharing files between devices on the main router and the remote repeater.
Mesh is in many ways worse than needing WDS. Almost all mesh systems only talk to stuff from...