How do I see which language apps other stores are using?

[Freejogger]

I am opening our store in a few days and I want to support multi currency/language right out of the gate, so I don't need to spend time redoing things later on.
Two sites that are using a translation app that I like the look and feel of are:
- lesdeux.com

- shapingnewtomorrow.dk

I tried looking in developer tools to find which app it is they are using, but with no luck. Maybe someone here has a quick solution or recognizes the language/currency selector.

Thanks!