Custom Binding is your friend.
You can set a custom binding type to show in sketchup that is different to what is rendered in VRay.
You do need to be able to locate the Sketchup textures on your machine, so have a little SU material library ready.
I have set up a small standard library of hatches that I use, or if I wish to use a flat colour I just set that as ‘Colour’ rather than ‘Bitmap’ in the Binding Texture slot of the VRay material.
You then have complete control over what SketchUp ‘sees’ and what VRay ‘sees’
I do this for every material I have in my model, I also use it to display ‘composite’ materials is SU, for example, If I create a texture map set from say, Substance Alchemist (Base Colour, Roughness, Normal, Glossiness etc) I combine the images in Photoshop to create a composite texture map that has Normals and AO and stuff like that baked in, which I then use as my custom binding texture in SketchUp.
