I am trying to input plurals for terms in all languages on one project. But I can only input plural on main language.

I am seen this image (https://s3.eu-west-1.amazonaws.com/po-kbpic/Language_Page_Arabic_Plural_Forms.png), but there is no option for this type of plurals.

Is there any way for me to input plural translate for all languages ?
Is there maybe some external software for your api ?

Please answer.
Thx :)