Yes, French criminal law applies to any offender who has committed an offense on the national territory, regardless of the nationality of the author and the victim (
https://www.legifrance.gouv.fr/affichCodeArticle.do?cidTexte=LEGITEXT000006070719&idArticle=LEGIARTI000006417187 - click on the article to access its contents). If you are a citizen of the European Union and you leave the French territory, a European Arrest Warrant can be issued against you so that you will be accountable for your actions before a French jurisdiction.