This is the most common point of confusion. The Epic Games Launcher is primarily a management and distribution tool.
Once compiled, you can copy the entire folder to an offline machine. The resulting UnrealEngine folder is a fully functional, self-contained build of UE4.27. However, this process is time-consuming and requires significant technical expertise. download full unreal engine 427 offline installer
I can provide the exact steps for the method that fits your situation best. Offline Installer of Unreal Engine - Epic Games Developers This is the most common point of confusion
Multiple machines can install the engine from a local network drive or external hard drive rather than downloading dozens of gigabytes on each machine. The resulting UnrealEngine folder is a fully functional,
Ensure your offline machine has the full offline installer for Visual Studio with the C++ desktop workloads pre-configured, or you won't be able to compile code projects.