Fake Brit: Australian Claudia Black as Cheetah, who's British in the comics.
Full Circle Portraying: Michael Rosenbaum provides Barry Allen's voice for the film, as opposed to Wally West like he did for the DCAU. Wally's original voice actor in the DCAU for his appearance in Superman: The Animated Series was Charlie Schlatter, who has provided Barry's voice for several animated shows and video games, beginning with the final season of The Batman in 2008. With this film Schaltter and Rosenbaum have portrayed both Barry Allen and Wally West, although the former has voiced Barry more while the latter is more associated with Wally.
What Could Have Been: George Newbern, who voiced Superman in the DCAU Justice League and Justice League Unlimited series, was actually supposed to play Superman here but he wasn't available so ironically Tim Daly, who voiced Superman in his 1996 solo series and whom Newbern replaced, played Superman instead for this feature.