There’s something else. It’s called lightmap mixing. Read this excerpt from the docs on reflections, and try disabling the “Reduce Lightmap Mixing on Smooth Surfaces” option in the Project Settings. I was wrong also, the lights should be set to stationary because it provides the best indirect specular and lighting data for reflections using capture spheres. Unreal Engine isn’t all too easy for some things. Sorry if it seems I’m misleading you with potential solutions. It’s often a trial & error process, but trying from a basis of knowing what’s involved / how it works.j
The link to the doc page:
May have to scroll down a bit to get to it after clicking.