Plugin for multilingual wordpress site

Hey everyone,

On my wordpress site I want to add more language versions. Ideally, there would be a switcher button, so after clicking site language will change. And menu with language options would be popup.Here is a site with a nice example. I like a solution when there is a popup, not just dropdown button in upper menu.

Does anyone know some Wordpress plugin? And please let me know if anyone knows how to build such a plugin.

Thank you