Hey there,
I was wondering if any of you knows, if at all possible, how to read inputs from this thing via an ESP32 with Arduino IDE?
Currently I am using a potentiometer with a DIY 3d printed assembly to have the same effect, but I would like to use something more robust.
I will be using it as a 'throttle' button for some servos/motors.
Pictures for reference:
The link: powertool triggers on Aliexpress
If you have other alternatives for the same function, I'll gladly hear them!
Thanks in advance for your efforts! 
How many terminals has the trigger got and have you tries measuring the resistance between pairs of them whilst operating the trigger ?
I have not purchased them yet, hence why I am asking.
From the description of the switches
Characteristics:
This switch is widely used in electric tools power controlling.
Built-in speed controller, plastic housing trigger switch. Features Lock on type, NO contact, SPST trigger type switch. Easy to mount on the power tool and easy to operate by pressing the button.
Despite being described as "speed controllers" the description makes them sound like simple on/off switches with the facility to lock them on. If that is the case then all you could do is to read the switch state which would not give you the ability to control speed
They are "cheap as chips" so why not buy one and see what it can do ?