You asked, we delivered. Support for Polylang plugin has been added and it’s freely available to everyone.
Polylang is a multilanguage plugin for WordPress and now it is fully supported directly in Newsletter core (no extension needed). With Polylang installed you can configure and translate every text, labels and emails.
Newsletters are composed using the posts extracted from the blog in the selected language to have a quick and reliable way to create a new campaign with the less possible effort. Polylang support is very similar to WPML support we published a few weeks ago.
Please take some time giving a look to our multilanguage support documentation page (it’s very short :)).
To be fully honest, we expect some minor glitches from this integration so feel free to report any inconsistency you may face during the use of Polylang and Newsletter. We’re in close contact with Polylang team which will support us making the integration as perfect as possible.