Can someone with a learners drivers license (from elsewhere in the EU) drive supervised in France?

Why do you think you would be OK? Most countries don't even know such "learner's license" or provisional license, and in countries where they do exist you're usually not allowed to drive without a person with a full license being in the passenger seat.

So almost certainly no, your provisional license will not be recognised as a valid driver's license by other countries. I don't know specifically about France, but in the Netherlands you'd get in serious trouble if stopped by police.

As to supervised practice, I'm pretty sure there's no laws against people with foreign nationality booking driving lessons. Which is what you'd have to do, go to a driving school and hire an instructor and car for a session.
Again, I'm not sure about the French situation, but in the Netherlands there's no permit needed to take driving lessons. You just have to be 18 years of age, and only certified instructors are allowed to give instruction on public roads (so it's the instructor needing the permit, not the student).

In france we can learn to drive from age 16 but it's not a license and you have to drive with someone who is more than 28 and has a license for more than 3 years, it's called AAC (Aprentissage Anticipé de la Conduite, Anticipated Driving Learning). So, a learners permit as described in the wikipedia article in jwenting's response does not exists.

I dont know if foreigners can enjoy this status as it requires to take classes in an official driving school and get a designated supervisor. What is sure is the pupil can not drive outside the country until he/she gets her definitive license.

I know that any EU citizens are allowed to get a license in any country of the union, according to local rules (for France you need to have minimum age 18 to be accepted to apply for the exam). That's a real (unlimited in time) license but our roadway rules have some specificity for junior drivers (no alcohol at all, reduced speed limits on highways, etc.)

Getting a license costs aroud 800 to 2000€ and much more depending on locallity and the school (some offers learning on really expensive cars for instance). But, if you already have 18+ and a license from your original country, it can be converted for much less money (it has worked for people I know with US and Lebanon drivers licences)

I am not aware of any provisions for that in EU law (nothing about that in the driver's license directive). I don't know about the opposite direction (i.e. coming to France) but I know for a fact that people doing supervised driving in France are explicitly advised that they don't have the right to drive in neighbouring countries (learners get a little booklet and an hour-long lesson/discussion with an instructor and the person(s) that will supervise them to explain what is allowed or not during supervised driving).

The provisional supervised drivers license is only applicable in certain EU countries. I am not aware of all the details for each country. However, when I took driving lessons I was doing an internship in another country. I wasn't allowed to even take driving lessons in my internship country at that time. You need to be eligible for a local drivers exam. Back then the requirement was that you need to be a resident for at least six months (next to a minimum age of 18).

It is an interesting question (either on expat or travel), what the current requirements are to do a drivers test.

To answer your question, a provisional drivers license is given in the context of a specific country. To be able to drive without a drivers license in another country you need to adhere to local laws, which in your case implies getting a local provisional license if such a thing exists.

If such a license does not exist (e.g. the Netherlands), you are not allowed to hit the road. In Belgium a provisional licenses exist, however it requires a theoretical exam and a minimum set of professional guidance before your are allowed supervised driving. As said in 1996 you needed to be a resident for at least 6 months to be considered eligible for driving lessons and exam. This might have changed recently.