<p>Well, you can say they're a lot like each other and that would be confusing, but they can work together if one of their mythologies is simplified. Personally, I prefer that it happens to the Eternals, because first: they are the ones who are based off the Olympians, not the other way around; second: many people do know the Olympians, their names and how they work already, because of how often Greek mythology is used in all other media, but the Eternals are unknown to the mainstream; and third: how many memorable Eternals are there, really? I don't know much about them, so I'm not someone who would be able to tell this anyway, but how many Eternals have done relevant stuff in the comics? Seems to me that the most important thing they could do in the MCU is helping to tell Thanos' origins, which yeah, is important, but after that, what exactly would they be used for?
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