Facing the Titan will be released in both French and English. But you don't have to choose yet. At the end of the campaign, I will send you a questionnaire. In this questionnaire, you will have to enter the name you want for the Hall of Companions, your DriveThruRPG account email.
This is when you will also tell me the language in which you want your PDF and Print-on-demand book.
So don't worry if you don't find where to set your language yet: this place doesn't exist yet.