I've had friends work at Sensibill[1] which sells tools (mostly to banks) to build some of what you're imagining having right into banking+expense tracking apps

I've had friends work at Sensibill[1] which sells tools (mostly to banks) to build some of what you're imagining having right into banking+expense tracking apps. Not sure if they have anything à la carte but they might have something of value to look at. 1 - https://getsensibill.com/ https://getsensibill.com/