Translate custom-post-type slug

First i want to take a moment to thank you for this amazing plugin.

I’ve read some topics that it’s not possible to translate the custom post type slugs. I found a slug translate plugin ‘https://github.com/KLicheR/wp-polylang-translate-rewrite-slugs’, it works ok, but it removes the locale from the url (very bad for seo purposes).

Is it hard to implement this functionality? Or could you point me to a direction?

https://wordpress.org/plugins/polylang/