Hi guys,
This had stumped me for a while, and finally figured out how to fix it.
read about it here poly-tonic letters to latin
I applied to v3. But it doesn't work. What is wrong? Altoght I tried to clean cache.
pcmemo if your cart already has products go to the products add-ons tab and delete the seo name, then save your product and the polytonic one will appear, if your cart has hundreds of products you could delete all the seo names from the database using phpmyadmin.
you can see it working here Ηλεκτρικές συσκευές | Homelike.gr the category name is greek, the url shows the equivalent Latin characters.
Thank you so much, I never figured out how to deal with this in my language…
your welcome 
Thank you, it works great.
glad i could help