MAC address

A Media Access Control (MAC) address identifies a network interface on its local network. It is commonly written as six hexadecimal byte pairs, such as 02:00:00:00:00:01. Apple explains hardware and private Wi-Fi addresses

One device can have different addresses for Ethernet and Wi-Fi. Some systems also use private Wi-Fi addresses that can change, so choose the address belonging to the connection you intend to use.

BetterDisplay's Wake-on-LAN settings need the target TV or receiver's network-interface address. Use the interface that remains reachable in standby. This is different from the IP address used to locate its control endpoint.

Sending a wake request does not confirm that the device woke. See Network Controllers for the controller-specific fields.