What you're basically asking for is a localised product based terminology respository. Or maybe it should only be product based if so indicated explicitely. We have no idea yet how to implement such a thing, or what it should be doing exactly. For now my advise is to create these manually as a subpage of your language portal, and refer from there.
A few remarks: "quick and small hacks" tend to turn into unworkable long term solutions. manually implementing this in qqq is not the way to go. There needs to be some process that will match words in the source message to defined terminology and translations so that everything works automagically.
I agree with the quick hacks thing, but I wasn't suggesting to manually(?) append these cheatsheets to the qqq messages, but rather to replicate that mechanism, with some changes in the pattern it uses to fetch the pages to transclude. This in principle addresses your concern about quick hacks -- unless the qqq thing is itself considered a quick hack. But if so, even though one wrong (is it?) does not justify another, I gotta say, while what you're talking about makes perfect sense and would be awesome, it seems like something that would take a while to be implemented (if ever). And on the meantime, maintaining consistency across translations stays a cumbersome task...