Hello Tim! The current generation of Eve Energy (AU) is not ready for Thread. We will be releasing new hardware generations of many Eve devices with Thread support later this year, but unfortunately can't give any further details on when this will be the case for Eve Energy (AU) at this time.
Here's a list of all the currently available Thread-enabled Eve accessories:
The only Thread border Routers for HomeKit are the HomePod mini and the upcoming Apple TV 4K.
Best regards, Volker
May 1, 2021