I always read this, but the last valkyrie was the easiest for me. Just had to remember how I did to avoid the attacks of the previous ones, and I killed her on the first or second try. Of course, it was only in normal difficulty (or hard? don't remember), but anyway, I had a lot more trouble with some other valkyries. The last one was a lot of fun though, can't deny that!
Oh, i played it on hard (hard is way more difficult than normal in that combat) and i needed hours of trying to beat her, with my best equipment, while the others only needed a few attempts. Every attack from her kills you automatically, and in higher difficulties she uses different attacks.
Playing GOW on hard or in god of war difficulty is a different and better experience than in normal. It's like with TLOU. I played directly the first time in hard, and every time you overcame a difficult section, the calm that followed was ...almost spiritual. Gameplay at the service of the story, immersing you in the game making you feel the same stress the character is going through.
I just checked, I was indeed in normal difficulty. I started a new game + in Hard mode, I need to keep going in this. Weird, usually I start my games in hard mode (like TLOU), guess I started in normal because it was my first game in a while.
But she never touched me during the fight, that's why I said she was easier than the others. She doesn't use the same attacks as the other valkyries in higher levels? In normal at least she's like a best-of, she uses one attack of each of the previous ones, so it's not that hard to avoid when you remember the other fights.