Since Webflow does not have any special multi-lingual solutions you typically have a seperate site for each language on Webflow.
You would simply create a seperate Webflow channel inside StoryChief for each language.

Webflow has added localization to their feature set as add-on, which allows creating new locales instead of creating whole new websites. 👉 Webflow University

In that case it's essential to match the StoryChief language code with the website's locale.

​This article guides you through the process of connection a Webflow channel.