awww is actually just swww renamed. The author felt guilty about the name because it was initially “the final solution to your wayland wallpaper woes”, and they weren’t aware of the connotations of “final solution” when they named it that.

Look at awww, it can handle transitions for you and is pretty easy to write a script for.

The website seems to work fine for me, but they seem to only support open hardware (e.g. Raspberry Pi or Mycroft). That doesn’t mean it wouldn’t work on other things though, especially with open software, but I wouldn’t be surprised if Echos require updates to be signed by Amazon, so it might require some hacking.