@mavrrick58 Agreed! However they are impossible to get on Amazon - and I haven't had good luck with Aeotec's website wrt delivery and updating of your order!
OK, well I learned I actually already have a device that does this. I thought I checked all my smart plugs but I missed some. These Iris 3210-L Smart Plugs report power use, voltage and frequency. They are also BOTH Zigbee smart plugs AND ZWAVE repeaters. The Zigbee part reports the power stuff and controls the outlet, and the Zwave part is just a repeater. You need to use this driver from Shackrat. Incidentally, it only seems to report voltage and freq when the switch is turned ON- which is fine for my purposes- I'll just leave it turned on.