Though I haven't used any recently, there are a number of 2-wire to Ehternet+POE adapters that would allow you to use the cresnet as a 'Category' cable and eliminate the need for Wifi connection.
Primarily for the CCTV up-conversion market (old analog to IP cameras) this would be my preferred approach as a wired ethernet connection has much less variables to deal with vs. a WiFi connection.
I know that DoorBird has a product, as well as a number of security/CCTV manufacturers...
