GFCI that notifies if tripped?

You could buid your own sensor and connect a dry contact relay to a sensor like this one with external connectors. If the power goes away, it will open the dry contact relay and change the sensor state.

https://www.amazon.com/Aeotec-Window-Contact-sensors-Battery/dp/B07PDDX3K6/ref=sr_1_3?dchild=1&keywords=aeotec+door+sensor&qid=1605882048&sr=8-3

Similar how you can connect wired smoke alarms: