Is there a specific word to describe the following type of mistake?
I asked your brother about it. Sorry, I mean, I asked your sister about it.
You can see it on the left. Wait, no, sorry, it's on the right.
She will be very happy to see Jonathan. Dang, did I say she'll be very happy? I mean to say she will not be very happy to see him.
They're not really blunders. And they're not typos either. Maybe slips of the tongue, but not Freudian slips, I'd say. But are there more specific terms to refer to such mistakes? You basically end up saying the opposite of what you meant, more or less.
Note that What do you call someone who substitutes one inappropriate word for a similar word?, a similar thread generating answers like malapropism and spoonerism, already exists but does not specify the inappropriate word being an 'opposite'.