The Honor Magic 2 stands out among new smartphones, as it is only the 2nd device in the world to be equipped with a slide-down display for a completely bezel-less screen. It was released in China on November 6, 2018. Now - only 2 days later - it is reported as completely sold out in the country's main outlets.
https://www.notebookcheck.net/The-Honor-Magic-2-sells-out-in-only-2-days-post-release.358001.0.html
Your not quite accurate with the magic being the only non oppo device with sliding mechanism..xiaomi mi mix 3 launched a week before the magic 2