Most actions aren't inherently good or bad, but I think it'd also be good to consider a view, where the consequences of your actions determine whether posting misinformation is fine or not.
Like, let's say the average internet troll makes a fake tweet, 10 people read it and no one falls for it. And let's compare this to a major news corporation intentionally fooling thousands of people on whatever topic. Both have the same intention, but for me it intuitively feels right to say the news corp was more in the wrong.
Actually a better example would be making a fake news article on april fools vs. not on april fools. Intention is to "fool the masses", but the severity of the situation changes (in my opinion).
When we determine whether something is moral by it's consequences, these dilemmas get solved. So therefore I don't think it's only intentions that determine whether something is a good or a bad thing to do.
Not saying this is a perfect approach either, though. And we still run in to almost the exact same problem, where tracking exactly which action has bad/good consequences is impossible, so drawing a precise line between acceptable and unacceptable misinformation is very difficult.
