This is way beyond what I can understand, but got me thinking: if a complex neocortex finally gets emulated and trained (current ML techniques) to a human level, how hard do you think it would be to implant primary directives?

Robot brains in Asimov's SF stories were designed mathematically, and they were mathematically proved incapable of defying the three laws. Our robots would be less certain, as its design would include too much randomness to manipulate with absolute certainty. OTOH, even Asimovian robots could defy the three laws if they knew enough philosophy.