Don't forget that correct (non-automated) translations and professional voice actors aren't cheap. The english voice actress is a blast and I hope they paid her well for the amazing job done.
In addition: I believe it's hard to rewrite the text so the charms that have different meanings depending on the sentence/situation stil fit during the situation the've been collected/added AND the blank spaces you can use them in.

Maybe they will add them when they have the financial funds like Return to Monkey Island did several months after the initial release. Maybe they think it's not worth to invest any more money into it anymore. Noone can tell without seeing the real numbers.