The short answer is: . But it comes with serious caveats.
Unreal Engine Portable: Can You Really Run UE5 From an External Drive? unreal engine portable
For users who need "portability" in terms of hardware, modern high-end laptops can handle UE5's demanding features like Lumen and Nanite. : The short answer is:
If your external drive is D:\ on one PC but E:\ on another, many references (especially absolute paths in .uproject files and SDK configs) will break. For users who need "portability" in terms of
Instead of opening the Epic Games Launcher every time (which requires an installation on the host PC), you can launch the engine directly. Navigate to Engine > Binaries > Win64. Find UnrealEditor.exe (or UE4Editor.exe).
Do not attempt to run Unreal Engine from a standard USB flash drive or an old mechanical external hard drive. The "bottleneck" will make the engine unusable. To run UE4 or UE5 portably, you need:
Yes, but pack a lunch (and a massive hard drive).