Wow! It just clips onto the HV cable and recharges while it’s hanging there. Presumably the drone has an inductive pickup coil that’s up against the conductor that’s carrying hundreds of amps. I bet Joe Tegtmeyer would like to have one of these!
https://www.facebook.com/interestingengineering/videos/1123581112297321/?mibextid=NnVzG8
https://www.facebook.com/reel/415716777728231?mibextid=9drbnH&s=yWDuG2&fs=e