Which DC superhero who was created by two high school students from Cleveland, Ohio has appeared in intercompany crossovers?
Intercompany crossover: In comic books, an intercompany crossover (also called cross-company or company crossover) is a comic or series of comics where characters that at the time of publication are the property of one company meet those owned by another company (for example, DC Comics' Superman meeting Marvel's Spider-Man, or DC's Batman meeting Marvel's Wolverine). Superman:  The character was created by writer Jerry Siegel and artist Joe Shuster, high school students living in Cleveland, Ohio, in 1933.
Superman