Weglot & Recipe Kit Integration
While Recipe Kit does provide a basic translation feature to change all recipe text as you need it (for example, if your store is not in English, you can change all recipe card information to your main language); the app does not provide multi-language translation features.
To translate the recipe content to more than 1 language, you'll need to use an app like Weglot. Weglot translates your entire Shopify store (including recipe cards and blog post content) into various languages, automatically. I've worked with Weglot to ensure that their app works perfect with Recipe Kit, and there are quite a few stores using both apps in combination to translate their recipe cards to other languages.
Check out Weglot here: https://weglot.com/