It’s like the goofy star, only in reverse star! In other words: the foot of the base is crossed over the shoulders of the flyer. It’s not easy, it’s an advanced technique.
Videos
The ascent is possible from the ground in the same way as the normal reverse star, only to an opposite half foot! Grigory Sapovalov
Goofy reverse star calibration, from one leg to the other. YogaSlackers