Those are assets that always gives warnings even if You open empty template. My plugin contains 2 classes, Blueprint Node Class and Custom Actor class without any meshes etc. After that I made blueprint based on this actor with single Sphere component and made 1 colour basic material. There is no possibility that I’m referencing this anywhere in my code or assets.
I will try to search for any of those and try to fix those warning tomorrow but I don’t think that’s the case.