You may be right RC but if this "power" that is calling out to Baylon and we follow the history of Star Wars story lines
then could it possibly be Palpatine that he senses?
I do not think so only because it's a different galaxy. But I could be wrong? Whatever the source of power is it is has the nightsisters eager to leave their home planet of many generations. They are not the types to abandon their territory without some kind of extreme threat.
Palpatine's manifestation post-ROTJ appears to be exclusive to Exegol.
https://starwars.fandom.com/wiki/ExegolWhereas Peridea is an Extragalactic location far, far from Exegol, which is located back in the original galaxy...
https://starwars.fandom.com/wiki/PerideaThere is a theme of death/dark side elements very prevalent on Peridea...
-The rings of the planet are made from Purrgil bones.
- There are giant monolithic statutes honoring some kind of figure. They appear to be the same or similar. I do not know if they are built to honor nightsisters or something...else.
-There appears to be other ancient structures dotting the landscape; temples similar to where Thrawn parked his ISD. Or the stone structures near where Sabine was ambushed by raiders.
I do not know if these structures are associated with the nightsisters or not. From an architectural standpoint...they seem very ancient.
-It a mysterious planet with a vast desolate and barren wasteland.
This came out after my post...
Ancient dark side Zeffo make a lot of sense!