You can't "adapt" to "kinetic energy". There are no voodoo "wavelengths" or "frequencies" you could "remodulate" to. If Borg could adapt to kinetic energy they could also adapt to being stabbed with something sharp or having their skull bashed in. Or to having a rock dropped on them. And that is just retarted.
And even speaking in game mechanis, as Kalavier points out, they don't adapt to mines or being hit with your rifle butt. Because you cannot adapt to that. Because if you apply enough force, their stupid space zombie skulls pop. End of story.
Actually, all stuff (matter and energy alike) has a wavelength. Quantum physics and stuff.
A standard force field can stop bullets. I'm thinking "Fist full of Datas" with Warf's gun fight solution. Also when in a brig why can't a person walk out. They have to push hard and it can stop that kinetic damage.
Also bullets on a holodeck may be based on kinectic damage but it is stil made of photons and force fields meaning it is also energy damage. The only reason the photons and force fields can cuse any kinetic resistance is because the force fields are like solid objects which is why the brig works.
It probably optically fooled the drones in first contact so they probably werent ready for it. also those drones may not have been fully assimulated and were made in hast since they were still wearing uniforms under their armor unlike Picard when he became Locutus of Borg. All they found was his uniform when they traced his comm badge.
The only problem with re-modulating cold is all you can do is change the temperature. Cold is a lack of kinetic energy. If you go by the kinetic molecular theory. all that gun can do is steal kinetic energy from its victims to simulate what we view as cold.
You can supplement potential energy to create kinetic energy. That is why a person can maintain heat by moving is cold weather conditions.