Ironically I really love both Norse and Greek as well! I've always kind of loved Norse mythology since I was younger, but didn't truly get into it until
God of War came out. I'm also a big dog person, so I personally loved Haati and Skoll as well as Fenrir, and find their respective stories fascinating. (Also quick side note, I do love the two most recent God of War games, but absolutely hate the combat T_T) I think I'd like to go back to Norse mythology to learn more about it, but I'm currently more interested in Greek mythology.
My love for Greek mythology really started to bloom when I first started playing
Hades (since I missed out on the Percy Jackson movies, I had NO interest in high school learning about it lol). I don't usually do dungeon crawlers, but the way the story progresses with the player and represents the Greek Gods absolutely resonated with me. This game legitimately resulted in me going to Wikipedia to just sit and read about the numerous different Greek Gods (namely ones having to do with the underworld, unique, I know). I definitely haven't learned all there is to know about Greek mythology, but I'd love to in the future. I think Hades has done a really good job of introducing me to the mythology, as I literally had no idea who anyone was other than the obvious figures like Zeus and, of course, Hades.