So we can see from how they meet.

you can see from the beginning they already have attention for each other, oh wait.. they started from enemies to friends do you get it?

Valkyrie saves him from being eaten by those weird colourful group of mask people, that is the starting, then he electrocutes him, yes i know that valkyrie sold him to the grandmaster, that is mean but then, at the end they develop a friendship between them and also help each other to defeat Hela right?

To start a relationship you need to make friends with that person first then know things about each other right? Valkyrie knows Thor is the prince of Asgard even before he told her. Wow.

"valkyrie knows because he shouts "HEY IM THOR SON OF ODIN AND I NEED TO GET BACK TO ASGARD!"

Um, nope, valkyrie didn't even shock or "omg it's thor!" she didnt even react so happy or scared or something. And she knows that he is a fighter maybe because based on his looks or maybe because because she already knows who is he.