I simply use an USB conference speaker/microphone plus the Assist Microphone add-on. (in my case this one from Microsoft, it works great with my RasPi.)
I actually prefer that over the Echo or other embedded devices, as it is able to pick up my voice from further away and the output audio quality is much better. (My use case is something similar to commercial proprietary systems like from Amazon/Google.)
The M5Stack Echo I use on my night stand with push to talk for quick actions, for that it is enough.
In the images for the left and right eye, they gave the vampires slightly different pupil colours. That means when you watch it in 3D, the eyes of the vampires kind of shimmer ominously. It works great because it’s only such a small detail. A larger area would be unpleasant to watch.
I’ve never seen another movie doing something innovative like that with 3D.
Edit: Here I found an example that can be viewed via crossy-eye method.