Amazon uses an ASIN system that connects items to the proper conversion chart. For example, if you sell Nike shoes under a given ASIN, they will be assigned an official Nike conversion chart from Amazon's library.
Our translations use the same process so your international listings will have official Amazon size conversion charts. For instance if you are selling a particular brand, an official size conversion chart from this brand will be automatically used in the translated listing.
We strongly advise against adding sizes to your item titles. Amazon has strict title creation rules and can suspend your items if you add sizes to your listing titles.