Regression: Tested in UE5/Release-5.0, this issue does not occur so it is a regression
Appears to be an issue with Lumen and Skylights with Cubemaps. Directional lights, point lights, etc. all work properly with translucent materials.
Actual Result: Sphere with the material renders completely black instead of receiving light from the Skylight and Cubemap.
Expected Result: Translucent sphere should render visible due to the light from the Skylight and Cubemap
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-170729 in the post.