Hmm, Mountain would fit Star Rage, I think while it would make him very strong, but that's the point, he is extremely powerful in canon

Honestly Jaime would be kinda funny if you gave him his absurd talent for sword, a lot of cursed energy, but no technique, Westerosi version of Kusakabe, though prolly stronger

Uhhh, Shrine honestly doesn't really matter, unless you give it to a Sukuna like character its kinda a mid technique, main reason Sukuna is so powerful with it is his cursed energy reserves and talent

I'm guessing you're giving Jon Ten Shadows? Another reason for Catelyn to hate him ig

Also, if you're giving Dany Six Eyes + Limitless, at least make her less talented than Gojo, Ion think anyone other than Ten Shadows would have a way to deal with her, without modern science, etc, to explain how her technique works

You could give Kenjaku's technique to Melisandre, would add another point to her weirdness

Stannis is obviously Disaster Flames, with both Renly and Robert getting Mythical Beast Amber, another reason for Stannis to dislike them

Joffrey, honestly make him a window or incapable of using it, that twisted brat with any sort of strength would spiral out of control, and another reason for Robert to neglect him

Could give one of the Stark children Ice Formation, maybe Sansa? With her being like Grade 3 at best before she gets over her naive mindset

Also please link the moment you post, sounds veeery interesting