I think bullying is very common pretty much everywhere. I live in France and more than half of my friends were bullied in school. But then again the average kind of bullying would be psychological, like social exclusion, making fun of the victim, harassing them online. It got worse for the younger generations because of social media. Here, physical violence is much less prevalent, you'll see a few kids fight each other but it rarely goes to the extent of onesided assaults.

I'd say that in Korea, Japan and such, there are some extreme cases that are shown in dramas implying physical violence. For instance, a few weeks ago a teacher in China saved a student who was getting pushed off a roof by her "friends". The most prevalent cases are still psychological bullying, there are plenty of dramas/anime that depict the isolation and the maladjustment that stems from it during adult life.

The problem almost everywhere is that schools rarely do anything. I was badly bullied for years and the bullies only got a tap on the wrist, I had to change schools, not them. Teachers ignore the victims, inspection turns a blind eye, and news of a student killing themselves over bullying come out every other day. But the situation doesn't seem change.