Hello, Few Months Ago, the Developer tell us (French Player), The French Translation will be out in 2018 with or after the Multiplayer Patch. The Year is about to end but we still waiting for it :'( I post a thread here, for asking if someone have news about that. Thx in advance.
Even the French eShop troll French Player. They post an picture with french word for the multiplayer update :'(
https://www.stardewvalley.net/whats-in-store-for-stardew-valley/ From the latest update to the developer's blog, it looks like CA is aiming for a French translation in early 2019, along with a few other languages.