Of course Sonic wears the Barry Allen suit because Barry is the only Flash with any sort of mainstream presence and you gotta pander to the people who only know DC characters from movies and TV shows and have never read a comic book in their lives. The only things Wally West have going for him are the comics and they're tanking in the sales charts. DC, just bring Barry back, okay? Nobody will complain.

August 2024 Comic Book Sales Rankings - Comic Book RevolutionComic Book Revolution

Also, Keanu Reeves has voiced both Shadow and Batman. Talk about a lucky coincidence.

Shadow the Hedgehog (Paramount)Sonic Wiki Zone

Bruce Wayne (League of Super-Pets)DC Database