How do i short leverge 'funds'

I dont mean buying the short leverage, i mean the actual etf.

If you look at nio 3x long, and look at nio 3x short they are both 99% down even though NIO the underlying stock is at all time lows.

Therefore you are in a win win situation if you short leverage funds over a very long time

I’m probably being stupid but if theres a way i bet people have been doing it