I think you have to change some ingame settings as well. I have my mousewheel up bound to stance down(not prone). To make a perfect dropshot I hold S to stop movement then scroll up to basically spam stance down.
I made it in for Logitech (Ghub/Gaming Software) but the overall way how it works should be similar for other programs too.(Also O is my the second key for stance down if you're wondering) . The hardest part honestly is getting the right timings between key presses but the macro itself isn't that complex:
You can also try doing it manually first, recoding that and then adjust timings.
Have a look at my ****** video, maybe it helps you understand it better ¯\_(ツ)_/¯
