Hi
Nearly three years ago, on the Calibre editor forum, we discussed the usefulness of spellchecking elided forms. Here is a comment from the maintainer of the Grammalecte extension for the French language about this topic and a way to deal with it for its language. Hope this helps.
https://www.mobileread.com/forums/sh...0&postcount=47
Note: French mainly use typographical (curved) apostrophes, at least for literary texts.