I've been using a z-stick for indigo and a SmartThings Hub to connect alexa to z-wave devices.
ST is junk and I hate it.
It also forgets most of the z-wave devices and it's impossible to reconnect them (plus I find that most z-wave devices hate having more than one hub)
Anyway, is there a hub that can work with both indigo and Alexa at the same time?