Think of this fan as as two motors in one, a low speed motor and a high speed motor. Each motr has it’s own Load(winding) wire You’ve got to switch power to the low speed wire, or the high speed wire. A three position Single Pole Double Throw(SPDT) Z-Wave switch doesn’t exist**, so you need to use two Z-Wave switches.
You could use two Aeon Labs Aeotec Z-Wave Micro Smart Energy Switch, 2nd Edition (DSC18103-ZWUS) each wired to power one of the Load wires to the motor. But, this is clunky and relatively expensive.
A more consolidated solution would be to use one either a Vision In Wall Z-Wave Micro Switch, 2 relay or a Enerwave ZWN-RSM2 Z-Wave Smart Dual Relay Switch Module to switch the two load wires.
The important thing to remember with this setup is that it is possible, even easy/likely, to have both relays on at the same time and this should never be allowed to happen. I’m unsure if it would seriously damage the fan, but it certainly is a possibility. Both Load wires should never be energized simultaneously.
To avoid both Loads being energized at the same time, I would manage the switching with PLEG, using logic that would not energize one relay, if the other was already energized. But, I would also create a couple of regular simple “safety scenes” that are triggered by the turn On of the relays. When a relay is turned on, the scene is triggered to immediately turn Off the other, regardless of its state.
**Edit: It seems that the Philio PAN07 can be used as a SPDT switch. I’ve never used this relay and don’t have a U.S. retailer that I can offer.