Lois & Clark does kind of have the same style. Maybe it's the WB lot that does it. Besides, Metropolis is often portrayed as brighter and less gothic than Gotham, so I don't think there's necessarily a conflict. And on top of that, we saw the Burton Batmobile in
Lois & Clark, presumably stolen from Batman.
Well, I guess the DCAU had a similar difference in design between Gotham and Metropolis. Still, I don't see that much similarity in style.
I could see a connection but always dismissed it because one show is live-action and the others are animated.
I don't see why that should be a dealbreaker. Several live-action franchises have had animated continuations that are meant to be in the same reality --
Star Trek: TAS, Star Wars: The Clone Wars, Godzilla: The Series, etc.
Doctor Who has a couple of canonical animated installments,
The Infinite Quest and
Dreamland (the latter of which had a sequel in
The Sarah Jane Adventures). The
Batman: Gotham Knight anime anthology is meant to be in the Nolan Batman continuity. There are even rare cases of animated franchises spawning in-continuity live-action continuations, like
Ben 10 (although the first live-action movie was later retconned as an alternate timeline -- but still part of the overall multiverse) and
Code Lyoko.
Mark Hamill as the Trickster in both was a nice touch though.
But it wasn't just Hamill playing the role, it was the same version of the character -- same costume, same mentally ill characterization (a little tamer, but that's because he'd been on antipsychotic meds for years by that point.)
Ah! Didn't know that The Flash had Superman and Batman posters. That kind of kills it. Awfully generous of you to let that go.
My point is that there are equivalent contradiction in other DCAU productions, and those contradictions have been glossed over by the producers and fanbase alike in order to keep up the pretense that
Static Shock, S:TAS, and JL are in the same reality. So if the others can be glossed over, so can this one. It would be a double standard to say otherwise.
Of course, the '90
Flash features Barry Allen and the DCAU features Wally West, but Barry passed on the mantle to Wally in the comics, so there's no reason he couldn't have done the same in that reality.