Change diffuse color of multiple different materials

I have angel wings with 100+ feathers all of which have a grey color in the diffuse color. I want to make them all white but they are different materials and I don’t want to link them because they each have unique UV meshes each with 2 textures that are UV meshed uniquely).

Is there an easy way to only change the diffuse color of all these materials to white?

Add the diffuse shader to a node group (Ctrl+G) then add that group to each material. If you change something in a group it will change for all materials using that group