Hello. I have a spare picade hat I’d like to use via usb as a controller if possible same as the picade pcb.
Is this possible or is the only way to use this by plugging it into the gpio pins?
You must plug it into the GPIO pins. It has no onboard IC to translate from GPIO to USB.
It’s possible you could accomplish this with a Pi Zero, or some sort of USB-enabled microcontroller, but it wouldn’t be trivial.