Add an option to show translate button for *all* posts

**Is your feature request related to a problem? Please describe.**
Sometimes I see posts that are not in my language, but there is no translate button, because the post is tagged in a wrong language.

**Describe the solution you'd like**
I want an option to have a translate button on every single post, even if the metadata says that it is already in the language I want to translate into.

**Describe alternatives you've considered**
Copy&pasting the text into another translation service, but this is inconvenient.