If you have French citizenship, you can work anywhere in the European Union, Norway, Iceland, and Switzerland. Some companies might make you switch your license over to the local country, which is usually just a paperwork exercise, but the country of license issue, as long as it is EASA, will not restrict you from working in one country or another.

As an example, Ryanair has hired pilots of all nationalities from Europe with licenses issued by all countries, but they require all pilots to switch their country of license issue to Ireland once hired. Mostly just a paperwork/money exercise.