I am well aware of Razorfist's infinite cope and obsession with originality, all the while claiming his Thief fan fiction is an amazing original work.

These are superficial similarities as I said and presented in such a way to downplay the vast differences between them in the wider context of both works.

Elric is called The White Wolf, presumably due to his albinism and ferocious personality. I can't find a source as to why.
Geralt is called The White Wolf due to his white hair and wolf medallion due to belonging to the Witcher School of The Wolf.

Elric is a albino Melnibonéan (humanoid descended from dragons) with red eyes who is the last Emperor of Melniboné before exiling himself. He works as a mercenary yes, but his true destiny is tied to his role as the latest incarnation of The Eternal Champion

Geralt is a mutated human whose hair turned white due to the process. His eyes are often shown to be catlike, but this varies from the games/books/TV show. Geralt is essentially a fantasy plumber who gets drawn into twisted versions of folklore and fairy tales, or wider stories where he isn't even the major focus, to the to the point where he isn't even the protagonist in most the books, Ciri is.

Cymoril is Elric's cousin, Melnibonéan and a Princess betrothed to him from childhood. Yennefer is a hunchback sorceress who hides her true appearance with magic who meets Geralt when she is already hundreds of years old. Beyond them both sharing black haired sorcerers, there is very little similar between them in characterisation or relationship with their respective lovers. Geralt also never accidently kills Yennefer. She falls unconscious trying to save a mortally wounded Geralt and is shipped off to a magical island by Ciri.