Tagging and crossovers
I've noticed a few fics where my fandoms will be tagged as crossovers, only for one or two of the characters to show up very briefly. In a few cases, they were gifts for people, so I think what happened is that they wanted to gift their recipient with a cute cameo from another thing they liked. Which is lovely. The trouble is that other people are also going to read it, and it's a better use of their time if they know whether or not the other fandom actually features.
I actually wrote a fic where I featured a character from Heartstopper, Nathan Ajayi. Nathan (a teen in the fic, not Mr. Ajayi yet) really only shows up in two scenes. So I tagged it "Heartstopper reference" and "Heartstopper cameo". I probably could have gotten away with tagging the character, though, since he does play an actual role and there are ties to HS. So I might have been overly cautious.
Now suppose I wrote a fic where two characters from another fandom went to Paris, and several pages in, they pass two teachers leading a group of students, and they share a brief exchange with Nathan Ajayi and Yussef Farouk before moving on. They never turn up again in the fic. That wouldn't really be a crossover. It's a cute wink and nod to anyone in the HS fandom, but the characters from my fandom aren't going to mean much to anyone in the HS fandom, and the mention of Mr. Farouk and Mr. Ajayi is so brief, they could be anyone. There's really no need to tag them.
I'm sure it's sometimes just clickbait, especially when I see 100 fandoms mentioned. But I'll give people the benefit of the doubt and assume at least half of the time, it's a tagging issue. (And again, when they're gifts, get it. They're trying to do a nice thing.)



