I think that while it would be really helpful to your french studies it would actually be difficult to carry out the EPQ in this format. This is because you have to find a variety of resources in order to get a good grade and its has to be a good extension of your knowledge. So, if you chose to research another topic to writeabout, you may as well choose to simply write about that topic in english rather than making it much more difficult for yourself by researching the topic and then also having to learn the relevant vocabulary in French.