Leg poses in a twisted grip handspring

Hi girls! I need some tips on how to execute certain poses while in a TG handspring. The first one is mermaid legs or bodywave. I know that when I'm doing it aerially in an upright position the movement originates from the chest but while upside down I find I dont have any mobility in my upper body so I cant make the wave travel nicely through my body. The second one is fang legs which I've seen Karol do from an TG extended Aysha but I think that her bottom hand was thumbs up as opppsed to the grip you would use in a TG handspring. Advice on these two moves would be greatly appreciated!