I found a solution without Servertravel. Just add a dynamic material instance for all actors in the indoor scene and add a “Lever” 0/1 alpha to the material that changes color brightnes in day night cycle
but there is some other Problem
to add the Indoor scene i use this node
and in Singleplayer it works fine
but if i tried on server the level is not load for the player it seams the level itself is loaded but the actors inside the Level are not valid for the player ( not visible no collision). NPCs of the indoorsceene level they spawned after from the BP inside the inddorsceeneLevel are visible and it seams they interact with the indoor sceene level (it is invisible but they walk in the sky so i think there is any floor with collsiion for the npcs)