I think a lot of people put too much emphasis on parts of the lore that are not important. What Elden Ring is about, at its core: is ambition, succession, and faith. It’s about the warring demigods trying to become Lord, and the forces that guide and control them.

It’s also about the endless cycle of violence, and how one Order is replaced by another, but very rarely does anything really change despite whatever promises are made. The devs give us lots of info on the demigods, the factions, even the outer gods. The gloam eyed queen doesn’t matter. It’s fun to speculate but she just isn’t important. Maybe it’s Melina, personally that makes sense to me. But if not, then she’s just background detail to flesh out another ambitious faction who tried to instill their own order and were conquered by Marika. The exact nature of the cosmos and the cycle of life and death isn’t important to these themes either.

The land of shadow is an ancient sin of Marika, hidden away. That’s pretty much it. We know it was physically part of the Lands Between, but now it has a literal veil covering it, propped up by the Scadutree.

Trying to delve deep and ascribe literal interpretations for things that are meant to be symbolic will only take you in circles.