No one has any idea what the song says in french.
The reason is - it's not french nor french canadian.
It was supposed to be, but the woman who sings it has an accent from the Bronx or something and murders the lyrics. It sounds pretty and french-ish, but really, no one I know who speaks french understands a word of it.
If you scour the web, you'll find some interesting translations. One part appears to be about birds and tree branches, and she is not echoing what the male singer is saying.