I add and control alexa devices and alexa smart home devices to homey. Then control them from the app / flows, its great for devices which homey can not natively support but alexa can.
I say ‘smart home devices’ but the only smart home device I have used it on is as I said the diffuser :
https://www.oittm.com/Oittm-Smart-Wi-fi-Aroma-Essential-Oil-Diffuser
Which has a Tuya chip in it, adding it directly to homey makes the token alexa is using invalid - so this is a nice work around.