https://wolfgangherget.de/powerline-coupler-firmware-rescue/ I found the solution for same issue on my 4010 here if you want to try it at your own risk. I've added a post to document this however...

Model : Hardware Version : Firmware Version : ISP : I had a TP Link 4010 powerline which failed to update a firmwareand then apparently bricked on a reboot. I spent a while trying to find a fix on...