Hi Rui,
Thanks for the reply!
This is awkward. I am facing this issue for the first time in my wordpress practice.
Unfortunately such a conversion will not work in my case, because the website will be multi-language and most of the taxonomies are using international names, which will cause conflict in both languages and there will be category slugs like “partners-1”.
For now I will try this solution, but still all permalinks will use this “transliterated” format, which is not good.