Spider-Man: Across the Spider-Verse was rumoured to feature cameos from the live-action Spider-Men and, while they didn't happen, Tom Holland's web-slinger at least received a mention.
Tobey Maguire and Andrew Garfield's respective Variants, on the other hand, appeared courtesy of archival footage from 2002's Spider-Man and 2012 reboot The Amazing Spider-Man.
One of the sequel's editors, Andy Leviton, recently took to Twitter (via Toonado.com) to share an in-depth explanation of how Garfield's Peter Parker was added to the movie.
What you might assume would be a relatively straightforward process was actually incredibly complex and, unlike The Flash, Spider-Man: Across the Spider-Verse didn't end up pulling any clips from YouTube for its big "cameos" (instead, it made use of footage directly from Sony's archives).
The movie's live-action elements surprised many fans, and Leviton would later confirm there were never any discussions about animating Maguire and Garfield's respective web-slingers. Given the explanation provided, we'd assume this means any possible future cameos would also be live-action.
That would require Holland, Maguire, and Garfield to film new scenes in costume rather than stepping into a recording booth, so we won't be holding our breath when it comes to seeing them swing into Spider-Man: Beyond the Spider-Verse...