Grin sells a unit that consist of a BB assembly (replaces the shaft for the pedals), and their Cycle Analyst display. It read the force on the pedals and converts it to a toggle signal. Your controller need to have a throtttle input. Quite complicated, expensive, and out of stock anyway.
https://ebikes.ca/shop/electric-bicycle-parts/torque-sensors.html
There are a few bikes that have overly strong level 1 pedal assist. BigAl is correct here. Learn to start without power. Learn to keep a finger on the brakes to cut power for low speed maneuvers. Or start with throttle before pedaling. When you get used to the ebike, you will eventually be riding a little faster, and it will seem OK. My first ebike felt like that, but I got used to it, and now it seems slow.
EDIT: Didn't realize Aventons need the pedals to spin before the throttle works?. On a 750W ebike? Crazy.
However, I won't stand for it on newer ebikes. In my last case, I swapped in a better behaved controller with a cadence sensor. Required a new display. Cheaap, but still complicated, About $100 and I got to draw on years of electrical experience to put it in.