Try adding
Super::PostEditChangeProperty(PropertyChangedEvent);
either before or after your other code.
If that doesn’t help, then it’s probably an execution order thing, with your changes getting stomped on by the construction script and component recreation. Other possibility is to override OnRegister:
void UNodeLocatorComponent::OnRegister()
{
Super::OnRegister();
LocatorRoot->SetRelativeRotation(RotationOffset);
Locator->SetRelativeLocation(LocationOffset);
}