Read the thread. Any Homeconnect capable machine will do.
Beware, this is quickly getting way more complicated than it seems at first glance: it is rather simple
to make a non-smart machine smart (enough), BUT even with a smart(ified) machine is not trivial to determine when to run the washing. You will need some kind of energy yield forecast mechanism.
Ultimately you will need a full blown EMS (Energy Management System) to get that right else you will not get the savings in the long run that you are hoping to get from this.
(Advertisement) I’m selling an openHAB based EMS appliance to handle this.
See also this thread.