I am using an automated script to translate several of my sites into a dozen languages.
The translations range from passable to truly awful. My Spanish readers don't seem bothered, my French readers are livid.
This strategy adds about 30% to my bottom line, so I don't really care what the French think about my abuse of their language.
AdSense ads are generated in real-time, so they cannot be translated. But, it's no worry. Google displays French ads to site visitors coming from France who are looking at French pages. It's all automatic, there's nothing you need to do.