User blog comment:MakeShift/Discussion on post-Crisis changes to the wiki/@comment-28109177-20200120070102

YES!!!! Supergirl confirmed everyone on Earth Prime are their former counterparts and the histories have been the same on Earth 38's part up until the Earths merged (Rhea's invasion, Kryptonian Witches, The Worldkillers and Reign etc.)

And J'onn DID in fact give Alex, Team Arrow, Ray and others all of their memories back, not just the Crisis.