This is taken from the
Epic Games Support site here, check out their Support site for additional assistance with the EGS launcher itself. This will also allow you to add Steam friends to your Epic Games account:
- Login to your Steam account in the Steam client.
- Login to the Epic Games Launcher.
- On the right-hand side click on See all above your friends list.
- Click the person icon with a plus sign.
- Click on Steam.
Note: If Steam doesn’t appear as an option, you will need to sign into Steam on your computer then restart the Epic Games Launcher.