I'm trying to get a cool display for the buttons pressed on my usb (Xbox One) controller, I've seen it on others' streams, and I'm beginning to think its just custom made for each person with API, which I know nothing about.

I'm sorry if there are other threads about this, I didn't find any, and I'm having trouble finding exactly what I want.

Most people use this: https://gamepadviewer.com/

I saw this, but it doesnt look COOL lol

I suppose I want the overlay to be a snes controller, as I usually do snes games, but, how could I also design one for like gbc games, etc?

i used padpyght in the past. its old an hadnt been updated in like 9 years but it should work. it doesnt come with a snes skin so youll have to make it yourself by editing an existing skin

I still use open joystick display, but it's not actively updated anymore. It looks like you'd have to compile it from source from github. It is customizable to look like a SNES controller though.