The Flash trailer was pretty cool. As annoyed as I was that they were redoing Flashpoint, it looks like they're taking a very different approach from the TV version, so at least it won't feel like we've seen it before.
One problem with the TV version is that the bulk of the story in the comics is about how the entire DC Universe is altered in a cataclysmic way, and the story is largely about exploring all those alternate versions of Batman, Wonder Woman, Aquaman, etc. The TV version was done back when the Arrowverse only had a couple of shows, so it was focused pretty exclusively on Barry's life with a glimpse at the
Arrow characters. So with all that extra stuff stripped away, it was just another iteration of the overused "City on the Edge of Forever" premise where the hero makes things worse by trying to fix the past and has to undo it in the end.
I was going to say that made it not very interesting, but then, I didn't find the full-on DC-continuity version in the animated movie
The Flashpoint Paradox to be much more interesting. I just generally don't like the story.
Zod being such a big part of the movies I surprise, I think I do remember hearing about Micheal Shannon being back, but I just assumed it would be for some kind of small cameo.
Is he really a big part, though? All the shots of him seem to be from one sequence, where Kara confronts his forces. It seems like a fair amount of the story takes place in a timeline where he had no opposition from Superman, but the focus might be more on the consequences of his invasion than on Zod himself.
Whenever time travel is involved it all goes to crap soon. By its very nature no one can establish rules and make them logical or constantly follow them to the letter, sooner or later there will be plot holes.
The laws of physics and logic establish clear rules of how time travel would and would not work, rules that were more or less followed by
Avengers: Endgame, or by fixed-timeline stories like
The Final Countdown and
12 Monkeys (film, not series). Basically, no event that's happened can be "erased", which is a physical impossibility and a logical contradiction, so any time travel into the past must either be part of what the original history was all along, or else creates a parallel timeline that coexists alongside the original rather than replacing it. There are plenty of time travel stories that follow those rules (including every non-
Star Trek time travel story I've ever written).
The model where a new timeline replaces/erases the old one is the version that falls apart logically if you think about it too much, but it's the one that's generally preferred in fiction because it creates higher stakes if the characters' existence or the world as they know it is in danger of eradication, or creates moral dilemmas if the characters have to choose only one of two competing timelines. Fixed-timeline or parallel-timeline stories are more limiting, but those limitations can be used creatively and effectively (see the
Gargoyles animated series, for example, or the aforementioned
12 Monkeys).