Of course, the Unknown God isn’t the first character with a name taken from Ars Goetia, with Genshin Impact’s Paimon also sharing her name with a king of hell, along with Genshin Impact Zhongli’s Archon name (Morax), Genshin Impact Raiden’s Archon name (Baal), Genshin Impact Vent...
However, remember that several of the archons in the game have names taken from demons – for example, the archon form ofGenshin Impact’s Ventiis known as Barbatos, who also appears in Ars Goetia as both the eighth pillar and the Earl and Great Duke of Hell. Plus, different cultures h...
Version 2.5 "When the Sakura Bloom" Trailer - Genshin Impact Ei acting as archon in her Story Quest Ei's Statue of The Seven Notes ↑ Beelzebul, although not in the Ars Goetia, is occasionally an alternate name for the Goetic demon Baal. Additionally, Beelzebul appears to be Ei's equival...
(Traveler): We finally got to see one of the the Seven Archons, didn't we? It was interesting to see what kind of god he was.Paimon: Hmm... Haven't we known Venti for quite a while now?(Traveler): As Venti, yes... But still, this was the first time that we got to see ...
Nahida has access to the Ars Goetia names of all the other archons (or at the very least she is the first person who mentions Focalors in game); so it's well within possibility that Rukkha's is in there too. And as I've said, a reincarnation does not make them exactly the same...