Idk if the just is only implied, but a translation without should be accepted as well, or not ?
I think there's a big difference in meaning. I don't kiss anybody means you are not kissing anybody, you're kissing nobody. But Jag kysser inte vem som helst means you're picky with who you kiss. Maybe you could make the first one in English sound like it meant the second thing if you said it with the right intonation, but how is the owl machine supposed to hear the difference? ;)