The global actor info map is not completely cleared in UReplicationGraph::InitializeForWorld, which can leave stale actor references from the previous level (WorldSettings, and possibly others) after a seamless travel.
Use a replication graph in a project, ShooterGame/Windows as an example.
Seamless travel between maps.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-67252 in the post.