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That said, I disagree with Den of Geek that the current rights situation would prevent from Amazon from including Fëanor if they wanted to. There's more about Fëanor in the Appendices—and, I'm pretty sure, the entirety of LOTR—than there is about Finrod, who of coursed show up in S1. Amazon would presumably have to invent most of this hypothetical Fëanor content, but that's not so different from the show as a whole (e.g., they couldn't call Sauron Annatar because that name doesn't appear anywhere in LOTR).
This seems like a bit of a stretch without any evidence other than the presence of a statue. ROP S1 had a bunch of statues of historical characters who (understandably!) didn't get flashbacks. But of course, things being a stretch have never stopped "some on the internet" from speculating.Some on the internet have speculated that the existence of the monument, as well as the other allusions to the character, could mean that a Fëanor flashback is on the way for the second season.

That said, I disagree with Den of Geek that the current rights situation would prevent from Amazon from including Fëanor if they wanted to. There's more about Fëanor in the Appendices—and, I'm pretty sure, the entirety of LOTR—than there is about Finrod, who of coursed show up in S1. Amazon would presumably have to invent most of this hypothetical Fëanor content, but that's not so different from the show as a whole (e.g., they couldn't call Sauron Annatar because that name doesn't appear anywhere in LOTR).