In my opinion, you need a 'Multi Network', a many Multi-Sites Network. I build them here and there for different languages for one country, like
domain.example/country/
domain.example/country/language-1/
domain.example/country/language-2/
domain.example/country/language-3/
The core of WordPress doesn't support them and you need an enhancement. Ready to use is only possible with the help of a plugin, I know - https://wordpress.org/plugins/wp-multi-network/ (https://github.com/stuttter/wp-multi-network)