I’ve been working on a multilingual site that has a product finder. We have 3 exposed filters that allow a user to select an Activity, IP Category, or Industry. All of these filters are Taxonomy Term filters. Some of the terms throughout those vocabularies have a specific language set, and should only show when that language is active.
The first step is to make sure the output (Views results) only shows products where the node language matches the current language. This is easy using the built in Node translation: Language = Current user’s language filter.