I did exactly this. Got an Eve smart plug meter and it works flawlessly in HomeAssistant. I'm also pretty sure I had upgraded to the latest firmware via Apple Home app before doing so.
Great, their new devices actually work in thread mode with HA, but their older ones only when you got an Apple hub device. I’ve got 6-7 of their devices before matter was a thing and 0 work with HA. Even those that got firmware updates.
Also: the Apple home app can’t change their mode to matter, you have to do that in home assistant.