Have you tried using WITH_EDITORONLY_DATA instead of WITH_EDITOR?
#if WITH_EDITORONLY_DATA
UPROPERTY()
bool bDisplayOverlap_EditorOnly;
#endif
The Unreal engine is using that around editor only properties.There is a short thread about it as well: https://answers.unrealengine.com/questions/48062/with-editor-vs-with-editoronly-data.html