Yeah it's called a "cut back" and it's used as a counter to a single leg when you are on your feet and your leg is in between your opponent's. You need to secure a whizzer (overhook) to make it work. You can either use your free hand to block the near leg at the knee as Sarikhani did or you can use the leg you are standing on to scissor kick the near leg. Both are effective and will take your opponent to his back. The scissor kick part is illegal in our scholastic style as you can really injure your opponent's knee. You can only attempt it using your hand to block the near leg.
You can watch the Polish wrestler Brzozowski attempt it here at the 1:37 mark:
It's nothing like a Metzger which was named after World Silver Medalist Andre Metzger.