Just a quick guide with some pointers that made the fights easier for me.
Gear mentioned in video and what I used:
Queens Crown (+3 int with no negatives)
https://eldenring.wiki.fextralife.com...
Metorite staff +30% gravity spells (Metorite and Rock sling)
https://eldenring.wiki.fextralife.com...
Carian regal scepter (with high int probably best staff in game)
https://eldenring.wiki.fextralife.com...
Talismans
Stargazer Hierloom (+5 int )
https://eldenring.wiki.fextralife.com...
Graven school (+4% sorcery damage)
https://eldenring.wiki.fextralife.com...
Radagon Icon (quicker casting speed)
https://eldenring.wiki.fextralife.com...
Metorite
https://eldenring.wiki.fextralife.com...
Adula's moonblade
https://eldenring.wiki.fextralife.com...
Terra Magicus (35% damage for 30 seconds when inside field)
https://eldenring.wiki.fextralife.com...
Flask of wondrous physics
Cerulean hidden tear (removes FP cost temporarily)
https://eldenring.wiki.fextralife.com...
Magic shrouding cracked tear (20% boost to magic damage)
https://eldenring.wiki.fextralife.com...
Adula glintestone dragon
https://eldenring.wiki.fextralife.com...
Alecto Black knife ringleader
https://eldenring.wiki.fextralife.com...
Black Knife Tiche ashes (Be aware cost 132 FP)
https://eldenring.wiki.fextralife.com...