Locate the most recent .item file. You can open them with a text editor like Notepad to verify it references your downloaded UE4 version. Copy this file to your external drive. Step 3: Install Offline on the Target Machine
As a mature product, UE4 (specifically versions like 4.27) is incredibly stable. Most critical bugs have been addressed, and it continues to receive "critical bug" support on consoles. Unreal Engine 4 Download Offline Installer
By default, the engine is installed here: C:\Program Files\Epic Games\UE_4.27 (or similar version) Locate the most recent