If any of you have already figured out a tool/workflow for this, I'd love to learn from your experience.
I'm finding language auto-detection to be a bit wonky (for example, it repeatedly identified Ladykracher audio as English instead of German). I ended up having to force a language instead. The only show in my library where this approach doesn't work is Parlement[1], but I can live with that.
On the whole this is looking quite promising. Thanks for the idea.