Well we also have some giant hornets in our garden and they do have the similar size.
My poor dog chased on of them and gut stung.
his paw looked horrible the swelling was huge.
I definatly dont want to get stung by these hornets.
Wikipedia says that these stings of the Giant Japanese Hornet are descibed as very painfull ^^

I hope i never will see such big bees...

Normally hornets do not do any harm to you, as long as you don't come close to their nest and don't make them aggressive. Wasps are by far more annoying and more aggressive.