I do not understand the point of “cosplayer in Equestria” (or “Displaced”) stories.
Like, okay, let’s talk a little about crossovers.
Like, first we have stories like Archives of the Friendquisition or Fallout: Equestria, where it’s sort of a blended setting that uses elements from the crossover’d material is used in an interesting way and the thematic juxtaposition makes for some interesting storytelling opportunities. Personally, I think this is the best way to approach a crossover.
Then you have lazier crossovers like, say, “Anti-Mage in Equestria” (which I hope doesn’t actually exist) where a character is lazily plunked into the setting for the sake of whatever plot. Hypothetically, this could be used to explore character - how does the character react to this setting? How does this setting react to the character?
But a “cosplayer in Equestria” story isn’t either of these. It’s just some idiot in a costume and also superpowers farting around. It is a crossover minus literally everything that might make a crossover interesting to read.