What about Android App Bundles' language support? You can find out everything you need to know about Android App Bundles here. As this is a new way to deliver apk's I am very interested in how it works.

When taking a look at the explanatory video provided on the linked site you will understand that the App Bundle will only send the appropriate language resource files on download from Google Play.

Now, what happens when I change the system language after installation? Will the application not translate even if in the original App Bundle there was my language packaged?
According to a Google I/O '18 talk Google Play will download all "typically used languages" and retrieve others on demand.


  In the rare case, where a user switches to a new language that we weren't aware of before, Play will dynamically deliver relevant splits to their device. (https://youtu.be/0raqVydJmNE?t=13m9s)