https://randomnerdtutorials.com/esp-now-two-way-communication-esp32/
I run a small collection of M5Stack components communicating in ESP_NOW.
A Core reading a Stamp for remote temp, the Stamp receives commands to operate a servo motor from the Core.
The M5Stack JoyC controlling a BugC unit is a good example as well, in the M5Stack examples GutHub.
Or my own GitHub repository:
https://github.com/teastainGit/ESP_NOWpeer2peer/blob/main/ESPpeer2peer/ESPpeer2peer.ino
has an example of one sketch that can be copied over to another device, change the MAC address and it works with each unit talking both ways with each other!