I was left high and dry with the Insteon shutdown, but HomeAssistant has saved me.
I dusted off an old, unused Pine64 and loded it up with Armbian. Instead of installing the Home Assistant Operating System or the Container install, I went ahead and used the Raspberry Pi instructions to install Home Assistant Core, and it worked! (Though I need to update the outdated Python).
I used emulated_hue to get Alexa working, setting the listen_port to 80 as described in the Alexa instructions. It failed until I allowed Python permissions to bind to that port.