I think this is possible with SPE. Something like this should work:
Remove-ItemLanguage -Path master:\content\home -Language "fr-FR" -Recurse
Perform this on a CM server and publish the site to move the changes to the web database and the CD servers.
It's probably also a good idea to rebuild your indexes and link database after doing this.
It might also be a good idea to set your language fallback already before publishing and rebuilding indexes, this way you only need to do that once.