ESP32 Mesh Network

Not personally tested yet, but looks very useful and promising.

Introduction

ESP-WIFI-MESH | Espressif Systems

Web app for testing

ESP-Mesh Resources | Espressif Systems

Practical example

ESP32 #84: ESP-MESH MESH and ESP-MDF – YouTube

Github repository

GitHub – espressif/esp-mdf: Espressif Mesh Development Framework

Comparison between ESP-NOW and Lora including power consumption.

#172 Hidden: ESP32 and ESP8266 point-to-point (ESP-Now): Fast and efficient. Comparison with LoRa – YouTube

Example with painless mesh. Some issues are mentioned in the comment.

ESP-MESH with ESP32 and ESP8266: Getting Started | Random Nerd Tutorials