There are no certified zwave/HomeKit bridges.
Originally, zwave.me intended to build one, but that was in late 2014 before the full specs on what being HomeKit-compliant would require came out.
(That was also around the time that smartthings, as well as many other companies, said they hoped to add HomeKit compatibility.)
Apple shut down that whole idea around February 2015 when they made it clear that anything that was certified HomeKit-compatible would require a special hardware chip as well as limitations on what features would be open. (so if you do any online research, pay no attention to anything to any company wrote prior to March 2015 about HomeKit. It won’t be accurate.)
This is why Phillips hue had to come out with a new bridge in order to get HomeKit compatibility.
Anyway, the only hub that currently is certified for HomeKit is Insteon’s HomeKit version ( which is a completely separate model from the regular Insteon hub). And that one doesn’t support Zwave.
I personally have both HomeKit devices and Z wave devices now, but they’re not all on the same system. I just use HomeKit with HomeKit, plus the Phillips hue bridge which works with pretty much everything.
All of that said…Everything in this post only applies to the officially certified versions.