Filter out things that aren't crossovers on Ao3.
Ao3 doesn't have a built-in way to only search for crossovers (works that involve two or more fandoms). This script implements that: while it's activated, any works tagged with only one fandom tag will be hidden from your results.
The method it uses to work out what's a crossover (simply: is it tagged with more than one fandom tag?) leads to some amount of false positives. For example, a fic tagged with Marvel Cinematic Universe and Captain America: The Winter Soldier would be shown, despite it not really being a crossover. However, the amount of single-fandom work which is hidden while using the script makes it worth using in any cases,
If you need the opposite of this, I've also uploaded a script which filters out crossovers. Don't run them both at once, though, or you will not be able to view any works.
