Yes, you can download the zip archive with the Highcharts code from our website or install the highcharts package from NPM. After doing this you can load Highcharts locally, instead of loading Highcharts over the internet.
Exporting
The exporting module is by default utilizing our export server and will try to make a request to https://export.highcharts.com, which will not work as intended without access to internet.
As an alternative you can use Client side export, or set up your own exporting server.