The first image shows the starting point. A road model that has defined the surfaces 1.3 and -1.3.

The second image shows how we want the result, as we have modified the textures for surfaces 1.3 and -1.3.

We click the surfaces, and change the texture directly in Properties, for example T_Asphalt07.

Edit the road model and click Result.

Change to Attributes Conversion per Feature. Change textureName to for example T_Asphalt07 for surfaces 1.3 and -1.3. Click OK, and rebuild the road model.