Wonder Woman:
Okay, so just before the events of Crisis on Infinite Earths, Princess Diana (of Earth-1) decides to chuck in the old crime-fighting gig and marries Steve Trevor (their wedding is presided over by Zeus, no less). She comes out of retirement to help fight the multiverse-destroying Qwrd the Anti-Monitor. Then, in the final battle during “the Crisis”, WW gets blasted with ‘anti-time’ that not only kills her, but unravels her whole personal timeline, so that she never even existed! WW being such a prominent part of the DC universe, this causes major chaos with the previously-established history of numerous ongoing titles - If there was no Wonder Woman, then who was Wonder Girl and what was her backstory? Who fought alongside Flash, Green Lantern, etc. in the JLA? Added to this is the fact that the original Wonder Woman of Earth-2 was similarly retconned out of existence by the big-“Crisis” shake-up, so there never was a Wonder Woman in WWII who served as secretary for the JSA!
Over the next few years, we learn that -
Donna Troy (Wonder Girl) who had previously been been found as an infant by WW, brought to Paradise Island and raised as an Amazon warrior and Princess Diana’s little sister, was actually the offspring of some weird alien race called “the Trojans” or something or other. She then changes her superhero name to “Troia.”
The Black Canary (who had her own cracktastic backstory) was a founding member of the JLA, rather than recruited as WW’s replacement (during the period in which Diana got heavy into her Emma Peel phase - but never mind that, since it now never happened.)
Back in WWII, an obscure little character called “Miss America” (no relation to the Marvel Comics character with the same name) actually served as the JSA’s secretary, not WW.
All of this is confusing, but (perhaps) forgivable since Wonder Woman gets a major reboot, reappearing in the post-“Crisis” universe as an “all-new” character (the New, New Original Wonder Woman perhaps), and her new series is not just good, it’s great. It’s one of the best late-1980s titles coming from DC, and WW reappears as one of the freshest, best redos ever (IMO).
Enter John Byrne.
Byrne decides that since the usual Batman, Superman, Flash & Green Lantern have all been featured in storylines wherein they have been waylaid and replaced in their superheroic identities, WW needs to be waylaid & replaced too! (never mind that Wonder Woman had just wrapped up a major storyline in which Diana lost the title of Wonder Woman and was replaced by a rival Amazon called Artemis for, like, a year.) Diana gets herself killed. The Olympian gods decide she was such an exemplary mortal, she deserves to be deified, and is ressurected as the goddess of truth.
Then Diana’s mother Hyppolyta takes a cue from Joan Crawford’s book and assumes the identity of Wonder Woman. She wears a skirt instead of short-shorts, and wields a sword & shield rather than bracelets & lasso. To make things even more complicated (!!!DAMN YOU JOHN BYRNE!!!), Hyppolyta-as-Wonder-Woman goes back in time to WWII and is stuck there for several years. Having nothing else to do, she joins the JSA as their secretary. And so, after having Wonder Woman’s WWII career & position in the JSA clumsily retconned out of established DC universe history, her WWII adventures and position in the JSA is even more clumsily retconned back in!
Oh yeah, that whole thing about Donna Troy being an alien? Nix! Seems that an evil biyatch stole a piece of the clay that Hyppolyta used to form Diana’s original body, and used it to make a ‘clone’ of Diana, albiet one approximately ten years younger than Diana. Why? I dunno, but given how convoluted things have gotten by this point, could there possibly BE a rational explanation?
Anyway, Diana is eventually un-deified and ressurected as a human being. Hyppolyta hands over the star-spangled bathing suit to her daughter, and is eventually killed by Darksied.
As for Miss America? Well, there were a few Phil Jiminez issues in which Diana goes back in time to WWII (GAKK!!), and in an effort to disguise her presence from the Hyppolyta-Wonder Woman, masquerades as Miss America…and temporarily joins the JSA when Hyppolyta-Wonder Woman is unavailable.
There is also another character called “Fury” who (pre-“Crisis”) was the daughter of the Earth-2 Wonder Woman. How they dealt with that character is beyond me.