Editor and NonEditor Actors using FindObject

I am finding ActorB(directional light) from ActorA usind method FindObject:

Light = FindObject<ADirectionalLight>(ANY_PACKAGE, TEXT("DirectionalLightStationary_TEST"));

In editor I see that this search is ambiguous and we have 2 objects - project and editor.
If I use string

"DirectionalLightStationary_TEST"

and play from editor - it affects on editor!
But when I use string

"/Game/Maps/UEDPIE_0_Sanctuary.Sanctuary:PersistentLevel.DirectionalLightStationary_TEST"

and play game from Editor - only game was affected.

Can anybody tell me why I have this behavior and what I should use for release project?

nullptr should be used instead of ANY_PACKAGE