September 2016 was quite a while ago. Here’s the edits you made that week. The edit to an “az” locale page does stand out, since the other edits were English.
The Revision history page for a localization shows the first English revision that a translation was based on. The first English revision was added a few months ago, along with first translation diffs sent to moderators. This allows the moderators to quickly see how many changes were made in the first translation. This can help determine when something was translated that shouldn’t have been, like the ID reference for a live sample. It also makes it easier to distinguish between good translation attempts and replacing a page with spam.
So, this translation has a single revision, and the history also shows the English revision it was based on.
One way these are created is when following a link from a translated page. For example, here is the homepage in Afrikaans:
It looks just like the English page. That community hasn’t translated any of the UI. If you scroll down to “Help improve MDN” and click on “Translating”, you arrive at:
Again, it looks just like the English document, except for the banner that says “Our volunteers haven’t translated this article into Afrikaans yet.”. If you saw a typo and clicked “Edit”, you would now be creating the first translation of the page into Afrikaans.
I don’t think there is any auto-creation of translated pages. I think people see these placeholder pages and create the first translation, not realizing that they aren’t editing the English document.