Thank you for sharing.
I hold my hands a lot like Joey does, more like in shoulder-hight than letting my arms "hang".
At 1:41/1:42 the one male person who wears black does a physical movement which is a strong stim of mine: when I stand upright I do not rock front and back, but I do this "rocking in a half circle with the upper body from side to side", do not know how to explain well.
He does it very short, but for me it is a real stim, for example waiting for the train to go to autism center or generally when I am standing in unfamiliar environment like in a supermarket.
Like the girl I am not very much talking, the boys seem to be more verbally and physically active.
_________________
English is not my native language, so I will very likely do mistakes in writing or understanding. My edits are due to corrections of mistakes, which I sometimes recognize just after submitting a text.