The ESP32 contains an Ethernet MAC.  To use Ethernet you need to add a Ethernet PHY IC.  The Espressif standard solution is based on using a TLK110 Ethernet PHY which is quite expensive.  The LAN8720 is a much lower cost option that can also be used. ESP32 Boards with Ethernet https://www.olimex.com/Products/IoT/ESP32-GATEWAY/open-source-hardware POE Resources https://hackaday.io/project/85389-wesp32-wired-esp32-with-ethernet-and-poe