Many interesting designs, but all of them use a form of rotary movement.
Even the one with the kite.
rotation is how you generate AC current. I didn’t look at the mechanisms in the wobbly stick but I’m guessing that at the base the angular oscillations are converted into rotational force. It just happens that diverting wind force with angles or generating pressure differences with foils is a more direct way to create rotation.
I looked and stand corrected;
“Currently, Vortex generates electricity through an alternator system, made by coils and magnets, adapted to the vortex dynamics, without gears, shafts or any rotating parts.”
Interesting.
I’m going to have to read more about how this works... if they are publishing the specifics.