OW MVP shut these frauds up
VAL > OW mechanicaly
https://www.youtube.com/watch?v=MGg94_9dDWU
Both games are just too different to compare. Hitting people in OW might feel/be harder, but at the same time its way more forgiving due to higher hp and you will get help from tanks and supports. While Valorant aiming might feel easier, but at the same time the enemies have it "easy" as well and you have to outaim or have better crosshair placement. For example in Valorant you sometimes have people who will just outaim you with ease, but that rarely happens in Overwatch unless they have some cracked Widow but even that isn't super common. You rarely feel like you are getting diffed in aim.
Both games are hard, but just in different ways.