To download Microsoft Visual Studio 2019 Community Edition for offline installation, you must first download a small "bootstrapper" file and then use a command-line argument to download the full installation packages (the "layout"). 1. Download the Bootstrapper
For the Community edition, you may still need to connect to the internet briefly every 30 days to refresh your sign-in, even if the software itself is installed offline.
How to download Visual studio 2019 offline installer - Stack Overflow
Copy the entire C:\vslayout folder to your offline computer.