Video of the issue here - [Link Removed]
4.27 and 5.0 seem to display slightly different outcomes. In 5.0 the sun only appears very close to the cube, whereas in 4.27 is can appear a bit further out of the vicinity of the cube. See video for 4.27, here is the 5.0 version:
Download the licensee repro from here- [Link Removed]
Issue should be visible in the editor in the same way as it is in the licensee's video.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-141193 in the post.