You can use “SetActorLabel()” in Blueprints to rename the Actor after spawning it. This will change the name of the Actor in the World Outliner, BUT this is only for in-editor use, you can’t use the Actor’s Label at runtime.
Also, I’m pretty sure you need to have the “Editor Scripting Utilities” plugin enabled in order for “SetActorLabel()” to be available in Blueprints.