Traduction en Français et German sont en cours sur le site du développeur :
https://risetoruins.com/index.php?/forum/16-language-mods-sharing-central/

J'ai installé la version Français, il est à 85%

The RtR website forums are old, outdated, and rarely used anymore. As for the latest localization mods, most of those are on Steam Workshop, so you'll need to contact the translation authors to see if they'll upload them elsewhere. There's a pretty good selection available there. As for options to download from the workshop without steam, that's being looked into.

Merci beaucoup (thank you very much),
Il fonctionne très bien après avoir donner les exceptions sur l'antivirus.

Translate it's :

Chinese to 100%
Spanish to 94,6%
French to 100%
German to 100%
Italian to 83,9%
Russian to 99,9%

there is a known issue, you can only display max. 8 different languages in the game.