A rule like that would not be useful for 99% of our users. Unless you’re writing in an academic context, putting just the year in parentheses does not really improve the text. It would have to be a picky rule (on top of matching only very rarely).
In an academic context, the resulting sentence would be hybrid, too. Either you talk about the book and the fact that it had been published, saying “O Rui aborda o tema no seu livro “Economia em Portugal” publicado em 2004.” Or you want to broad-quote it, then you’d go right for the quoted content and follow it by something like “(Sousa 2004)”.
So, I’d say it’s not worth the time, in principle.