The most conspicuous form of foreshadowing is the red-herring, a form of misdirection. Now, you might argue this isn’t foreshadowing because it’s leading you down the wrong path or it’s a false foreshadowing that it leads your towards a conclusion, though this conclusion may be incorrect. You might even argue that it isn’t false foreshadowing because it can suggest the answer it’s trying to make you look away from. Either way the red herring foreshadows an event, even if it isn’t the one you expect.
Red-herrings a usually associated with crime fiction because the traditional structure of crime stories requires some false clues to lead the detective away from the real criminal. These red herrings don’t have to be glaring clue, such as physical evidence, they can be something more subtle like a misplaced phrase. Whatever they are we know they’re going to point to a suspect and that suspect and the detective are going to clash in some way. In this sense it has foreshadowed an event, although that event is not necessarily the conclusion. It’s important to remember when we talk about foreshadowing it doesn’t simply apply to the conclusion but to any event later in the story than the foreshadowing itself.
Without misdirection a lot of stories would be far shorter because the path of the story would be more direct. Red-herrings are a useful way to introduce subplots though they can relate to a sub-plot without actually beginning a sub-plot. For instance a red-herring can lead the detective following the wrong suspect or can encourage them to pursue a suspect they already have in mind.
However, misdirection can be tricky to do. A red-herring often doesn’t work as effectively if it’s too obviously a red herring. The exception to this would usually be if there is a reason why our characters would follow the path suggested by a conspicuous red herring. There might for instance be place they trying to avoid, a haunted house for example, and then they spy a path that might lead them to safety through a patch of wood. A reader might see that this path is no less dangerous than another and think the character shouldn’t take it but if a character has a convincing motive following the alternate path might not seem as bad to them. They may even realise that it is a dangerous path, but that path is not as bad as the haunted house so they’ll take it.
In situations where people don’t have a preferred option bias, the subtle red-herring often works better so the reader doesn’t immediately realise that it is a red-herring. In a crime story a red-herring might be less satisfying if the misdirection wasn’t a viable solution; if the path offered by the red-herring looks like it could lead to a viable conclusion for a story the reader often gets more enjoyment from trying to guess if it is a red-herring. Trying to guess the solution of a crime story before the detective is what some readers enjoy most about the crime genre.
It isn’t only crime stories where red herrings appear but any story where we’re led towards alternate solutions. Although we don’t tend to refer to them as a red herring we might say that in a romance novel other potential suitors are red herrings, the enemy who isn’t an enemy in sci-fi or fantasy, or the riddles on a treasure map in an adventure story, IT’s possible to use red-herrings in every genre, in fact it’s probably difficult to write a story with no red-herrings.