Comment by pavlus

You make another drone swarm and hit drones with drones. That's how it's currently done in Ukraine with standalone small UAVs and multicopters right now, anyway. Shooting them is hard, net-shooting and shotguns work, but it must be automated, since there are a lot of them. EMP is a fairy tale, because you would also fry everything else, and the most common EMP used in wars so far is an atomic bomb. Jamming may work, if frequencies are known, and there is jamming equipment deployed for that frequency, but it's likely you need to jam video, as to not get operator to the point where they can make decision to be executed autonomously, and perhaps intra-swarm communication as well, in case of retranslators,as with a swarm it's possible to make multiple communication channels to the base, since different units can carry different sets of transmitters, so the best bet is drones hunting drones.