Local rotations of components are inconsistent between the Level editor and the SCS editor. The SCS editor rotates the transform widget's coordinate system to match the selected component in FSCSEditorViewportClient::GetWidgetCoordSystem, and FLevelEditorViewportClient::GetWidgetCoordSystem does not. This can be problematic if you have a hierarchy of SM components that you want to pose on a per instance basis in the level.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-86664 in the post.