[05]

ESP32 has inherent sleep issues and before their latest chip (c6 I think) 'deep sleep' was really a gpio- or rtc- triggered boot followed by a power off. Doesn't mean it's impossible to implement wifi sleep efficiently, but if you do the math anything wifi based won't work off cr2032 for even a year unless daily updates is all you need. Motion sensors are supposed to fire more often, and with much less latency that can be done via WiFi, so it doesn't really work for battery powered sensors in the general case. You could probably use ESPNow and a custom gateway node but at that point it's just another custom RF protocol and you're better off with something standard like 802.15.4 or BLE..

[cameldrv]

You can put the ESP32 into deep sleep, and it can wake based on a timer, or it can run the ultra-low-power core which is a very slow, very low memory, very low power core. It's good enough to look at ADC or I2C devices and do a little math. This can be woken up fairly frequently to check a sensor, and say, compare against a previous measurement, and then wake up the main core if you need to process the measurement or do WiFi.

I think you're right that this won't work well with a CR2032, but if you're careful about using good voltage regulators it can last a long time on 4 AAs.