I know a cynic will say "well thats what media does!" but no, it doesn't. Not at the level that the current breed of fake news and propaganda is doing. Exaggeration and taking things out of context are one thing (and in some cases nearly as bad), but totally inventing stories about people and using that to manipulate people is awful. I don't think "outlawing" it is the right way to go about it but there has to be a label that says "This is not a reputable organization" so that people that don't know better don't stumble in there and not know the difference and end up ready to shoot up a pizza place to save some imaginary children.
What has go to with this though is a totally open algorithm for declaring something fake news, essentially a non-partisan fact-checked breakdown of exactly how some source was declared to be "fake" and maybe some other automated metrics.
Granted, this will not catch the people who desperately want to believe the fake news or who already believe it, it is just to keep more gullible people from stumbling into the trap. Just like Chrome warns you when a cert isn't valid, why not say "hey you are leaving the beaten path of facts, proceed at your own risk". I'm not saying its up to google but search engines are a logical choice, but it has to be done transparently and there has to be an appeals process in case it was a mistake.