Chaos provides direct links for the material library based on your Corona version: Download Link Corona 10: Download Link Corona 9: Download Link Corona 8: Download Link
The can be downloaded as a standalone package for offline installation on 3ds Max (versions 2016–2023) . This is useful for computers without internet access or for batch installations on render farms. Official Offline Download Links
How to install the material library in offline mode? - Chaos
the file in the same folder as your Corona Universal Installer (.exe file). Run the Corona Universal Installer.
The installer will automatically detect the local file and install the library from your disk instead of attempting to download it from the server. Key Locations & Troubleshooting