All right, since Barry, the Flash of Earth-12, was older, they would call him "Big Flash."
The method he mentioned for taking everyone into the Speed Force Plane was actually quite simple: they would drive in.
Nearly every Flash, aside from Wally, had his own "Flashmobile," usually an ordinary sedan with a Cosmic Treadmill mounted on its roof.
That way, when a speedster ran wildly atop the car, everyone inside could be wrapped in golden lightning and rush into the Speed Force Plane, traveling to Parallel Worlds or different Time Points.
For Earth-0, however, traveling to Parallel Worlds had been replaced by Boom Tube Teleportation, while reflecting through the Bleed Layer was far more convenient. After the Flashpoint Crisis, Little Flash had also stopped messing around with Timelines, so he rarely took his car out anymore.
On other numbered Earths, though, they lacked the Mother Boxes needed for Boom Tube technology, so they still relied heavily on the Flash for rides when traveling far.
"It's great that you're willing to take us, but is everything all right on your side of Central City?"
Su Ming pointed toward the street corner, where a zombie staggered into view.
"Probably?" Big Flash instantly turned into a streak of lightning, grabbed the zombie, and delivered it outside the city before returning to Deathstroke. "Once we enter the Speed Force Plane, the current Time Point remains frozen relative to our coordinate system. We just need to find whoever we're looking for inside, then return to this Time Point."
Since the zombies still had human forms, the outbreak had begun too recently for their bodies to rot completely. They still looked somewhat human, so Big Flash could not bring himself to kill corpses that looked like people.
As the conscience of the Justice League, the Flash