Configure you SpatialMaterial
the way you want it (the features you need) then in the slot where your material is assigned, click the dropdown and select "Convert to ShaderMaterial". If you don't configure it first, you'll only get the basic shader code (without normal mapping for example).
As an aside: You can use the vertex color with SpatialMaterial
, look for Vertex Color -> Use As Albedo. This does multiply with Albedo Color and Albedo Texture. But maybe you're looking for something different?