Хмм.. Тогда понятней. Просто в вики описано иначе. Якобы можно для каждого языка определить свой шрифт
Set multiple fonts for different languages
If you are not a native English speaker and want to use another languages alongside English, you may want to set appropriate fonts for each language in your whole OS. In NixOS, it's so easy. Imagine I'm a Persian speaker and I want to set "Vazir" font to Persian texts and "Ubuntu" font for English texts. Just put these lines into your configuration.nix: