Where to add a power on/off switch to an ESP32 board with battery

@Wawa wiring the switch enable/disable deep sleep does seem like a viable option even though I would rather have it completely off.

@ShermanP thank you for the clue on the CHIP_EN pin it does seem to offer a way to switch off the chip, though I am not sure I would have it low by default. I will be reaching on Seeed forum for further help on that specific board (link).