Yes it‘s 100% local, but i cant remember whether its using bluetooth or wifi. And if you want to control it from remote a homekit controller will male a secure connection from your apple device to your home network by proxying encrypted data through apple servers.

From a Reddit comment: "The home assistant tp-link integration already makes use of the local api connecting to the devices. I'd definitely recommend using a reserved dhcp address and specifying the devices in your ha config (not using auto discovery)."

TP-Link devices do not require you to create an account. Please don't spread FUD.

They do if you want to use most of the functionality (e.g routines, scenes, connecting to a smart assistant, etc.) Using them without an account basically just lets you use your phone to turn them on and off.

I use mine with Home Assistant and don't have a TP-Link account.

Can't TP-Link plugs be flashed with firmware that allow for local-only control?

Yes, Tasmota: https://tasmota.github.io/docs/

Discussion on HN: https://news.ycombinator.com/item?id=24785175

Fortunately this is also true with many devices, but knowing which ones allow this before buying is the problem. Most shops won't advertise the chipset. This is also beyond the abilities of 99% of the population.