If I try to translate a field like this:
title:
label:
en: Title
es: TĂtulo
type: text
It doesn’t work, I have to specify the local Spanish variation:
title:
label:
en: Title
es_ES: TĂtulo
type: text
And then it only works for Spanish (Spain).
I suggest that the language code should work for all variations and just had to add the local code when there are differences. In the future, there could be more Spanish or English or other language variations.