I’ve been playing around with Hue apps for Halloween lighting as well. The Scary HueHello is a plug-in for the HueHello app, which must be installed for the Scary HueHello to work.
There are a few halloween themed Hue apps out there that have both ambient sounds/music, and short soundbite types of things and the Hue lights will sync with it. Thunderstorm for Hue, Hue Halloween, and Hue Haunted House Party are ones I’ve tried, and the sound does come from the phone, but it’s not limited to that. For an individual speaker, bluetooth is an option. For multiple speakers, and please keep in mind that I’m using Google Home speakers and Chromecast instead of Echo and Sonos, but I can cast the audio to a speaker, chromecast, or speaker group.
Some apps rely on the microphone in the phone to detect the sound for the lighting effects. So you’ll have to keep that in mind. But as long as your phone is within earshot of a speaker, you should be good.
After playing around with it, I believe I’m mainly going to use Thunderstorm for Hue from my phone, but may try to simultaneously run one of the other two apps to different speakers using my tablet. I should probably try that out first, though. I also have some non-Hue bulbs (Osram Lightify) that I may use simply in pulse mode or something similar.