I was going to post this as a reply somewhere, but I figured it could be its own topic: I really hate Wonder Woman being involved with World War II (or WWI). And I don't think her first adventures should be in the distant past.

As a start, it makes a mess of her supporting cast. Mainly Steve, but Etta is she's one of the first friends Diana makes when she leaves Themyscira.
But more importantly, it creates a lot of issues with her character that, while admittedly could make an interesting Elseworld story, won't be treated with the gravity they deserve.

Regarding World War II itself...for one, I just don't understand the obsession with keeping her origin there. Hey, guess what, Superman and Batman also fought Nazis because that was the thing back in the 40's, but we don't see an insistence of keeping their origins there, do we?

More importantly, Diana's stated purpose, her mission, is to bring peace and improve the world. So if Wonder Woman participated in WWII...she failed. She failed as a peacemaker. She failed as a hero.
As much as we (as a country--the United States) love to mythologize WWII because it was the last "good" war with clearly defined "bad guys" that were defeated...there's still the attempted extermination of the Jews, the atrocities the Germans and Russians committed against each other during their fighting, the (arguably) unnecessary bombing of Hiroshima and Nagasaki. Among many other things 'cause, you know, it was a freaking war.

Captain America in WWII kind of gets by because he's just a soldier fighting battles and he's not as powerful. But, again, Wonder Woman's stated mission is to bring peace. I can't imagine Diana allowing that stuff to happen, nor do I see them letting politics stop her.

But then comes the bigger question of what the hell she's been doing in the decades since. Because if you have Diana first appear in one of the World Wars (or earlier) you then have to get her to modern times so she can interact with the characters we care about. And surprise, it winds up being a cheap hand-wave that doesn't consider the long-term ramifications of Diana being Wonder Woman that long.

If creators are going to make her hundreds of years old and/or active since one of the World Wars, they do need to acknowledge the toll it would take on her. But it seems like writers wish for a Captain America type of thing where she fought in a World War and we just jump to modern day, but Diana obviously doesn't have the frozen in ice bit...so they just gloss over the fact living for a hundred years and watching friends and loved ones age and die around her should affect Diana.

Then there's the question of what Diana's been doing in the decades since the war, because you have to reconcile how/why a lot of nasty crap happened despite her presence. And, guess what guys, there is no good answer. There's a reason WW84 didn't even acknowledge what Diana was doing (or not doing) after World War I ended.
She either tried to improve things and failed consistently, or felt it wasn't her place to interfere and limited their actions to punching bad guys, reducing her to a milquetoast defender of the status quo.

I don't like the idea of her going back to Themyscira for a couple of decades and then becoming Wonder Woman again in modern day. Because, again, that should be treated with actual gravity. Diana quitting or just packing it up to go home should be a big deal. Something making her decide to be Wonder Woman again should also be a big deal.

There are potentially compelling questions to confront Diana with. How long does she really plan on being Wonder Woman? If enough time went by, would the job or watching her friends and loved ones age wear on her, and if so, what would she do?
As it stands, the only stories off the top of my head to even come close to addressing this is New Frontier and (to an extent) Kingdom Come. Should either of those be the "main" Wonder Woman? Remember how a key part of Diana's arc in that story is how she gets burned out and frustrated with everything to the point where she considers quitting?

Again, that can make for a compelling Elseworlds take on Diana. But I think it's a bad idea to make it the mainline Wonder Woman.

And, finally, at the end of the day, what is gained by this? Why is it so important to have Wonder Woman around in World War II? Yeah, we all love watching her beat up Nazis, but newsflash: they haven't gone anywhere! White supremism and neo-Nazis still exist today!
So she can have the "bragging right" of being the "first superhero"...as if that makes any damn difference? Hooray, more meaningless lip service that won't make DC treat her any better!
So we boast about her unparalleled battle experience...as if it's going to stop her from getting jobbed out like a chump in any given issue of Justice League?

I just don't understand the insistence on anchoring her to the 1940's. If Wonder Woman must fight in World War II for nostalgia or whatever, keep it confined to Earth-2 or an Elseworld. The "main" Wonder Woman should be in the modern day like everyone else.