>>35081111Green doesn't hate Red, but he's frustrated about the possibility of Red getting ahead of him because he's used to being No.1. They are somewhat alike and even had the same height, the possibility of Red getting taller than him also upsets him according to the manual iirc.
His behavior is clearly aggressive at the Pokémon League, I don't think you can interpret that any different. He also leaves Red alone is situations of peril.
We hardly know what kind of person Red is because he was an insert character, but I don't think he hated Green because Red is a selective talker and to date he only talks to Green. I guess that makes Green feel some pride.