Use CMake to generate the Visual Studio solution without needing an active internet connection for the build itself.
However, you can achieve an offline-capable setup through these two main workarounds: 1. The GitHub Manual Build (The Pro Method) cryengine offline installer
While Crytek primarily pushes its Launcher for updates and project management, several methods allow for a "standalone" or "offline-friendly" setup. Does an Official "Single-File" Offline Installer Exist? Use CMake to generate the Visual Studio solution
The most reliable way to create an "offline" version of CRYENGINE is to download the source code and its associated SDKs manually. cryengine offline installer
This method is preferred by enterprise teams who need a "frozen" version of the engine that won't change or require a login to run. 2. Using the Launcher's Offline Mode