Just build an own wrs with all the textures, and build another wrs with very small dummy textures, that you put in the server's folders.
But the server and client are using the same folders! It's the same binary, as I said above.
I know. What I meant is, that you send only the wrs with the dummy textures seperated from the game folders within the zip.
The dummy textures are supposed to be tiny.
Maybe, you can include two installers, one for client mode and one server mode, where in server mode the standard texture wrs will be replaced by the dummy textures. No different binary needed. Means: in server mode there are just different textures in the same folder.
Or: even better. Maybe, you can implement in the code that when starting as server the engine loads the textures from the dummy texture folder, and when starting as client load them from the standard folder - I'm not sure whether this is possible, though.