From the VLSC, you can download full ISO images of the multi-language packs, which contain all supported languages in one file. Installation Steps
If your organization uses a Volume License for Office 2016 Professional Plus: Microsoft Office 2016 Language Pack Offline Installer
The Microsoft Office 2016 Language Pack Offline Installer is a critical tool for organizations and users needing multilingual support without internet dependency. It is and requires a valid Office 2016 license. For legitimate offline deployment, obtain the installer exclusively from Microsoft’s Volume Licensing Service Center, MSDN, or Microsoft 365 Admin Center, and always verify digital signatures before installation. From the VLSC, you can download full ISO
The Offline Installer is essentially the entire language pack wrapped in a standalone package. It doesn't need to "talk" to a server to pull data during the installation process. It is the definitive solution for reliability. It is the definitive solution for reliability