ESP8266
NodeMCU v3 (image from https://www.theengineeringprojects.com/2018/10/introduction-to-nodemcu-v3.html):
ESP32
DevKitC with ESP32-WROOM-32 (image from https://gojimmypi.blogspot.com/2017/03/jtag-debugging-for-esp32.html):
Without DevKitC (image from https://randomnerdtutorials.com/esp32-pinout-reference-gpios/):
For WROVER, GPIO16 and GPIO17 on the devkit board is not connected, because the chip uses it for something else. (image from https://www.instructables.com/The-Incredible-ESP32-Wrover-From-Espressif/):