That sounds pretty interesting, I've never seen such a device before tho so it'll be a little hard tonfigure out
Most devices like the ones on sink have a battery, although you could get a little generator that could power the device when water is flowing
However leds and mostly speaker draw a decent amount and I think that will be hard to achieve without a battery somewhere
Idk if there a way to generate power from just pressure, but probably the generating device will also be your sensor on pressure