This is a known and reported issue UE-7019. Currently the bug is not on the immediate roadmap to be fixed, since not all lighting features are supported (or are intended to be supported) within paper2D. Another reason being the asset still functions the same when playing in the viewport or launching.
If you have any further questions please let me know.
Go into Project Settings → “Rendering” and make sure that Forward Shading is enabled. After restarting the editor, i had no more lighting problems.