It would be set in the Arrowverse, but not cross over because it would not work by my opinion. It would show Tom Welling Superman in Metropolis saving people and working at the Planet and what not. Gotham should also do this and called it Gotham: Batman Begins

In Smallville Season 11: Continuity, Barbara Gordon arranged a meeting for Bruce Wayne to meet her replacement, Dick Grayson, after she became a Blue Lantern. But if Dick is Batman's new partner, does that mean he's going to become the new Nightwing, or will he come up with his own name. TBH, if Babs was gonna be Nightwing in this universe, then maybe Dick Grayson could've been Red Hood.

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I want to see her in the new supergirl season. She appears commonly in the Trinidad Guardian issues of 1944, specifically as the last line of comic panels in the short comics section. (Found here; https://ufdc.ufl.edu/UF00081212/00503/allvolumes)

She seems to also refer to Lois as "Aunt Lois," which would be a good point to add in the show. Whoever's daughter she is, I think she would be a good addition, considering the 40s was a popping time for comicbooks and DC in general.