This technique looks crazy, but is actually related to a very functional (although flashy) move from the sitting on shoulder position that is one of the hub positions of the Omoplata attack system.
Detailed breakdown of the Sitting on Shoulder Position here: https://www.youtube.com/watch?v=cWSgEryiHlU
The Omoplata 2.0 trailer in 53 seconds: https://www.youtube.com/watch?v=P3qLV1ujet0
My complete Omoplata instructional here: https://www.grapplearts.com/omoplata
Original aikido clip available at https://www.instagram.com/p/Cv15ZnpxTL6/