And Batman is not the only superhero. Look at the movies. Look at the comics. Rarely. Vary rarely are they ever taken down. When they are, it's with guys with guns. Guns. Something incredibly more deadly than a sword. (And spare me the police lecture on knives versus guns. Any sane person would rather face a knife wielding bad person than a gun wielding bad person. And if there are multiple bad people, then knives would always be the answer.)
In the movies Batman takes out entire buildings of bad guys with guns. And he does it without even using deadly force. A consideration that supremely limits his "power." Geralt loses to a single monster. Not even a really strong one at that, all because he doesn't use deadly force. Batman fights alongside godlike status partners: Wonderwoman, Superman, Flash, Aqua Man. And he holds his own. In fact, much of the time he leads them. Geralt can barely convince a barkeep to serve him a drink. Then there is equipment: Geralt has a silver sword for monsters. Batman literally made a suit that could enable him to fight Superman.
There is no comparison as to which one of these people is a superhero.
Not to mention that Batman has the ultimate super power. Invulnerable plot armor.