As stated on the coreutils mailing list, the best way to proceed is to contact the translation maintainers or you won't be immune to a regression when the maintainer will push a update w/o the fix because there is version control system for the translations of coreutils.
I've updated the French translation of coreutils (from 8.9 to 8.12) in upstream (Jim have contacted the French translation project).
As stated on the coreutils mailing list, the best way to proceed is to contact the translation maintainers or you won't be immune to a regression when the maintainer will push a update w/o the fix because there is version control system for the translations of coreutils.
I've updated the French translation of coreutils (from 8.9 to 8.12) in upstream (Jim have contacted the French translation project).
Thank you for the report.