Google’s John Mueller said on Twitter that Google will still show your website in other regions if you use the geographic target setting in Google Search Console. This setting only helps Google understand that your website might be more relevant in particular regions.
Geotargeting doesn't restrict a site to only be shown in that location.— 🍌 John 🍌 (@JohnMu) November 12, 2019
Geotargeting doesn't restrict access, it just means we can promote it as local for folks searching for local results in that country. You need to handle this on your end. There's no option for search engines that restricts access from individual countries.— 🍌 John 🍌 (@JohnMu) November 12, 2019
If you want to block particular regions, you have to do that on your own server:
You'd have to do it on your end. There's no option to do this through search, for web-pages.— 🍌 John 🍌 (@JohnMu) November 12, 2019