Must the label be translated to the specific language of a country?

This depends on the country but often the answer is yes. For example in the Netherlands the local ordinance for fertilising products requires the label to be translated to the local country. So whilst the FPR criteria apply universally without national changes, the only topic you must check nationally when you ship the product is whether the label needs to be translated. 

You only need to translate it for countries who have such requirements and where you ship. 

For the Netherlands the label must be translated to Dutch.