Now I'm curious. Why does your wife hate WiFi? They've made significant improvements over the decades. Many have come in the last several years with the mesh systems that have really good performance and coverage.
Ethernet over Powerline will likely never touch what you could be getting via WiFi. I use both in my home. Many devices that I previously had difficulty reaching via WiFi used EoP. I have migrated nearly everything to WiFi now that I've replaced my router a couple of years ago.