Hi reefG,
We’ll probably add an explicit uninstall option to the launcher later, but for now you’ll have to go to a double secret location here, “~/Library/Application Support/Epic/UnrealEngineLauncher/Data/Manifests”. If you remove the manifest file for the corresponding content package, you should see it disappear from the launcher the next time you run it.
Cheers,
Nick (Epic Games)