: You can download the full engine source code from the CRYENGINE GitHub repository on a machine with internet and transfer it via external storage. This allows you to build the engine from scratch without relying on the Launcher's automated download.
In older iterations (CryEngine 3), the installation was much simpler for offline use: cryengine offline installer
or "offline redistributable" for the latest versions of the engine. However, you can achieve a "solid" offline setup using a manual file migration 1. The "Wedge" Method (Semi-Offline) : You can download the full engine source
The CryEngine offline installer is typically available on the official Crytek website or through authorized distributors. You can download the installer from the Crytek website, and then run it on your computer to install CryEngine. cryengine offline installer