First of all, I am not good at English, so please forgive me for using a translator.
In old UE4
When using World composition, various Sub Levels were used by streaming.
Some of the various sub-levels used various triggers to freely load and unload, giving various changes to the world.
However, when changing to World Partition, the Sub Level disappeared and the World change according to certain conditions became unavailable.
Is there any function that can change the world while loading or unloading with specific actors like a sub level?