Although I spent many years at Software Engineering, I am now asking for something I know nothing about. I have scanned through the Calibre files and dll's and can't make heads or tails of them.
So as I did when needed, I call in the experts.
Would it be possible to translate the Convertbooks into a plugin? This would give a one stop tool. Convertbooks does a fine job of translation. No need to reinvent the wheel.