I'm not entirely sure if we accept that Kaguya can see souls or not? If we don't then I can't see anything from Kaguya stopping Pernida from Hirenkyaku directly in front of her and crushing her physical and spiritual body into pieces with his nerves.
If she can see souls it becomes a better debate but even then I still have Pernida winning, most of her main offensive abilities; such as Ash-Killing Bones or Vacuum Fist are negated by Pernida's nerves switching the direction of the attack, him regenerating from the damage caused; creating more clones of Pernida or him just dodging with his Hirenkyaku.
Pernida will also, throughout the fight, get continually stronger, smarter and gain more abilities and resistances through the Compulsory; making a battle of attrition for Kaguya a dangerous one.
Pernida also has potent abilities like Heilig Pfeil, which spiritually and mentally erases people from existence when killed, completely negating Kaguya's regeneration. He can use Sklaverei to deconstruct and decompose Kaguya's physical and spiritual bodies on a Macro-Quantum level, and absorb her into him. Hell, even all of his attacks are infused with Soul Manipulation which ignores conventional durability.
I can see some arguments for Kaguya, I just believe the arguments for Pernida are better and easily more achievable compared to Kaguya's arguments.
