Use a multilanguage installation
Use en-GB for backend language.
Add proper additions in en-GB.localise.php so that non-Latin characters are replaced properly.
Create an article in tr-TR, for example and add the words 'İnsanlık' and 'ayrılık' as the tags of the article
Non-Latin characters in the tags are stripped. They become 'i-nsanl-k' and 'ayr-l-k' respectively.
Notice that system puts a dash if the tag starts with a capital i (İ).
Localization file is not obeyed.

Also the tags that are added within the article are assigned to the language 'All'.
They are assumed to be in the language of the article.