You really are being obtuse here.
Uh, try again, Sandra had it in the first story as did Starman. Again both are set in that era, one that I have pointed out repeatedly has more to do with other than the war.
From Comic Vine
Phantom Lady first appeared in Quality's Police Comics #1 (August 1941), an anthology title; this issue also included the debut of fellow Golden Age characters Plastic Man, Firebrand, and Human Bomb (all of whom later became DC characters). Though Quality's writers never gave Phantom Lady a proper origin story, they established her alter ego as Sandra Knight, the beautiful debutante daughter of U.S. Senator Henry Knight. She was engaged to a government agent named Donald Borden, who sometimes assisted in her crime-fighting exploits. As Phantom Lady, Sandra's costume was essentially a one-piece yellow swimsuit with a green cape, and her primary weapon was a "black light ray projector," which she used to blind her enemies and make herself invisible. Quality published Phantom Lady stories for 23 issues before the character was picked up by Fox Feature Syndicate in the late 1940's.
I was pretty sure Starman was never provided with an actual origin story in the GA, and didn't have one until Roy Thomas gave him one in All- Star Squadron.
They are not that workable for that era and as it is, why bother when there are a ton of characters from that era that would work far better then the anachronism you trying to make. You basically are trying to get a 52 Earth 2 with just the names and a little bit of the cosmetics.
First, you haven't given any evidence of an origin story so deeply ingrained in the 30's or 40's that it couldn't be updated to fit into a more slidable continuity. (The JSA's origin notwithstanding). I doubt that there's are a lot origin stories that couldn't be updated to where the essentials of the original story remain intact without the connections to a fixed historical era or event.
I haven't read Earth 2, so I'm not going to get into an argument there. I do know that what I'm suggesting is not as radical as some of the things Robinson has apparently done there.