how to total the size in disk space of Epic Games games i have not installed?

Epic Games Store didn’t offer a built-in feature to total the size of all your uninstalled games in your library. You would need to manually check the size of each game individually.

However, software and features may have been updated or changed since then, so I recommend checking the Epic Games Store for any new features or third-party tools that may have been developed since my last update to make this process easier.