Upon looking into the 'Done' button issue further, I confirmed that this is definitely not a Waze UI issue. These buttons are part of your keyboard, and are not controlled by the Waze app. The second example that is translated into French that you sent me is also a part of the keyboard.
I will let you know when the 'Send' button is translated.
Thank you for brining this issue to our attention, we will update the string ’Send’ to be localized in all languages. This should happen in the next few days. Regarding the word ‘Done’, this screen is not part of the Waze app, you may be able to fix this by setting the Web browser language to French.