HomeKit and Alexa controlling the same devices? (nanoleaf, iHome)

i know this is a weird place to ask about competitors devices, but everyone all seems to know so much! Before I continue, i’ve Already tweeted to nanoleaf and IHome and one hasn’t Replied while the other only kind of skim read my question and didn’t really answer it so I an hoping people here will know;

i have nanoleaf lights and iHome wifi plugs (series 6) and everything is set up to run off HomeKit and I have no plans to change that, however I got a free Echo Dot that I am trying to decide if I want to keep so my (I thought!) simple question is just this:

if I have these devices set up to run through HomeKit as the main and original owner, can I ALSO setup Alexa to control these devices IN ADDITION TO, or are they only one or the other, not both?

as I said, I already contacted Nanoleaf and got no reply and iHome simply says their products can be controlled by Alexa (because they didn’t really read my question) so would anyone know for sure the answer to this question? Thank you so much if anyone can answer definitively ( or just guess!)