Not a dcu person personally but I’ve read everything blackkat’s written ever, and she had some cool dc crossovers if I remember correctly

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There’s an old blue beetle YJ fic where they go to Oa that’s pretty solid and has fun Guy Gardner shenanigans: “A Study In Scarlet Scarab” by DreamStoryWeaver on fanfiction.net (Google the name and you’ll find it)

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