This Sheffield United player scored against Wrexham and then made this gesture. Based on context, it appears as if he’s mocking Wrexham’s players and/or fans by acting is if they’re crying – as in, “haha, waah! waah! I scored a goal against you! [raspberry]” Is that what it means?
I don’t know what it means in Soccer, but Bad Bunny does it.
In ASL it can mean very small or a little bit.
It’s his hand-crafted [heh] gesture of affinity to his fans. I suppose it’s being copied now.
You’ll get to see it in the Super Bowl next year!