Will it work for me?

Yes. You can still control lights from the Hue app, but then also gain local control of them from HE (Hubitat Elevation). However, the Philips Hue API limits the refresh time between the app and anything connecting to the bridge via their API. So you will not see changes made outside of the app reflected in the app for 1 minute. Best thing to do is to control them with Hubitat Dashboard, That way things will be in sync immediately.

You can continue to use both. I control my Harmony Hub via this community driver and RM rules, and I still use the Harmony app and my Harmony Touch remote anytime I want.

Correct. As @aaiyar pointed out, Alexa/Echo is a purely internet connected device.

Sorry. Fixed in my previous post, and here it is again.

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