This is great. Recently got an xteink x3 and jailbroke my kindle, making custom stuff for it.
I couldn't find it exactly in the docs. Sorry if I missed it.
If you align these and then pull onto koreader via opds or other way, will audio work over Bluetooth there too? Along with the highlighting.
You can use a KOReader plugin, https://github.com/stradichenko/audiobook.koplugin, which has work-in-progress support for Media Overlays (the EPUB spec that Storyteller uses for readaloud)!