Access to material itself from blueprint?

hi
I hope to know if there are ways to access material parameters from BP ,(not as the instance material. and all objects which assigned the material can be changed )

Picture above,
I only could change the selected one,prefereable result is all the spheres are changed to black.

You can use a material parameter collection and control it via the level blueprint.

thank you .
I think i can do with it .

i will find how to connect “selected sphere” and “parameter collection”.