An offline installer is only as good as its maintenance. To preserve the highest quality:
If you have access to a computer that already has UE4 installed, you can manually move the files. Locate Files: Navigate to C:\Program Files\Epic Games\UE_4.XX Copy the entire version folder to an external drive. unreal engine 4 download offline installer extra quality
Use Visual Studio to build the engine. Once done, you can move that folder to any offline PC and run UE4Editor.exe directly from the Binaries folder. 3. The "Sneakernet" Method: Manual Migration An offline installer is only as good as its maintenance