@Wayne-TP Thanks--done all that: removed from Kasa, re-added, etc. Alex can't find it. The phone is inches from the device, so it's not connectivity (plus Kasa would have trouble if so, presumably).

  @Greybeard3 OK, there's definitely something weird here. On a whim, I did the factory reset thing on the third plug that didn't reconnect. Alexa immediately saw it and let me discover and configure it, and now it's working. Didn't need to set it up in Kasa at all, as indeed I didn't originally for most of them.

I had ordered four more of the same Kasa plugs anyway; when they arrive today, I may return the two "bad" ones, as there's clearly something weird about them. It's not like this reset business is that tricky--I'm sure I'm doing it right, especially now that this third one worked!

It sounds like you're expecting to have to add them in Kasa before Alexa can see them. That's not always the case, at least for me. Firmware, maybe?

  @Greybeard3 New box of Kasa EP10s arrived, and all seem to connect fine without the Kasa app. So I'm going to return the "bad" ones. Weird. Thanks for the input!

  @Wayne-TP OK, but but but...with FFS I don't need to ever go to the Kasa app. And that's what worked for all but a few plugs, and didn't work for them even after a factory reset. I sent them back so it's moot now but still seems wrongish!

  @Greybeard3 Adding to this thread since it's the same set of plugs: today I got an Alex notification that a plug had been detected and added. Weird. Sure enough, "First Plug" was there. I poked the power switch and heard the switch click (lucky, I happened to be in the right room!) Did that a few more times, figured out that it was the one previously labeled "Fire Stick". (We have an Amazon Fire Stick on such a switch because occasionally it wedges, and this lets me power-cycle it without having to pull the dresser out to get to the plug--yeah, lazy.)

And sure enough, "Fire Stick" was gone from Alexa. Now what would cause it to randomly reset like that?! No power hits, and there's a second identical plug in the same outlet, which is working fine.

  @Wayne-TP Nope, don't even have Kasa installed any more. Now, I might have added a plug with that name to Kasa at one point when I was having trouble, but not THIS plug.