For Context: The Eternals is a Jack Kirby series, revolving around a group of beings; created by the celestials, that live for long periods of time.
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That said, there were other individuals on the shortlist, including apparently; Travis Knight (Kubo/BumbleBee); Nicole Kassell (HBO's Watchmen) & Cristina Gallego and Ciro Guerra (duo for the last two).
Also, upon looking more of the backstory; this might be the way they may introduce X-Men & Mutants, due in part to the Deviants.