There is an ESP8266 baby monitor project that streams audio in real-time.
https://perso.aquilenet.fr/~sven337/english/2016/07/14/DIY-wifi-baby-monitor.html
Nowadays it might make more sense to use ESP32 and i2s MEMS microphone. But I have no experience with i2s microphones. (ESP8266 || ESP32) + i2s microphone = WiFi bug