“The Primus says: Zovaal pursuels the secrets locked within the Sepulcher. Should he find the knowledge he seeks, all that you know will be undone.
The Primus says: Four sigils represent the renewed hope of the covenants. I will use them to forge a key… though I must find something to replace the Arbiter’s sigil.”
You can read it all here
I don’t think that’s what it means. At all. Each sigil was remade once a covenant came together and did… something. I don’t know why this would mean Sylvanas would be the new Arbiter.
Sylvanas is not an Eternal One.
However, Elune is…
Elune is not an Eternal One. She’s from the Life Pantheon. She has no claim over the realms of death beyond her relation to the Winter Queen.
Please cite reference.
Elune can’t even show her face in all these years. She’s too shy to do anything.
They are connected through the Great Cycle that we learned about in the Grimoire of the Shadowlands.
I’m failing to see anything in this text that says WQ and Elune are not Eternal Ones.
Also mind you, you are quoting a source that starts out with the following words:
Ardenweald’s functions support our theories…
Miss that?
I’m an Eternal One.
Prove me wrong. I haven’t seen anything that says I’m not.
When I die, I come right back. That clearly supports my theory that I am.
/flex
I didn’t say the Winter Queen wasn’t an Eternal One. She is.
Elune is not. As evidenced by the big bold letters saying “PANTHEON OF LIFE”
The Primus also says that Elune is the Life counterpart to the Winter Queen who is of Death.
“The Winter Queen is bound to her counterpart in the realms of Life.”
Ok, let’s dissect the text here. It states first, that these are theories. We already know their theories are wrong when we look at their maps of the cosmos.
That established, let’s look directly at the text. It states WQ is an Eternal One in the Pantheon of Death.
So why would Elune being in the Pantheon of Life disqualify her from being an Eternal One???
Even if it’s a theory it’s also backed by the Primus literally stating she is from the realms of Life and is the counterpart to the Winter Queen.
Because the Eternal Ones are the names given to leaders of the Pantheon of Death.
https://media.discordapp.net/attachments/406285497846071306/869682952215355392/unknown-8.png
Also here’s the Primus outright confirming she’s not an Eternal One.
Cite reference please.
All the references you need right here.
Titans aren’t called Eternal Ones so why would Elune?
Ok, so you do realize that WoWpedia is a player created database that uses in game lore without speculative content right?
So given that the only in game information on what an Eternal One is can only be used. So at this point in the narrative that has been given us, the only names we have been given for Eternal Ones are those listed there. This does not in any way imply they are the only ones, or that the Pantheon of Death is the only pantheon populated by Eternal Ones.
You tread dangerously close to the sort of speculation that creates head-canon.
Arguing that Elune is not an Eternal One based on a lack of evidence that she is does not prove your point.
You’re being pedantic and obtuse at the same time. Congrats.
How am I being pedantic and obtuse for asking for information? If I’m wrong I want to see the source material so that I can learn. If that’s being obtuse then I don’t want to live in your world.
All hail Vincent!
Or… you’re really a banshee. 
edit - would we really want to hear the scream of a Tauren banshee tho? 
In order to be considered a counterpart she would need to be the same as the WQ, just for the world of the living. So be declaring her a counterpart (and the fact that the WQ legit calls her a sister) points to Elune being an Eternal One.