Hi there,
I just tried to load the Google Fonts used on the website of our client locally via his webserver and NOT via the Google servers.
Therefore I identified the fonts, downloaded them, put them (EOT, SVG, TTF, WOFF, WOFF2) via FTP in the /wp-content/themes/x-child/fonts folder and added the ‘fonts-CSS’ code to the CSS via Theme Options.
Afterwards I used the plugin Autooptimize to remove the Google Fonts. By checking via Google Chrome > Sources I can still see the entries fonts.googleapis.com and fonts.static.com.
Then I changed the body and headings font in Theme Options > Typography from ‘Open Sans (Google)’ to ‘Arial (System)’, checked again in Chrome, but no changes.
Where is the mistake?