Log in to the portal, navigate to Unreal Engine > Downloads , and set the "Type" dropdown to Unreal Engine Offline Installer .
The offline installer for Windows is typically distributed as an .msi file inside a .zip archive, which can be run directly on the target machine. Alternative: The "Local Backup" Method unreal engine 4 free download offline installer
If you do not have enterprise access, you can "create" your own offline installer by transferring a pre-installed engine folder: Log in to the portal, navigate to Unreal