Specifically for inquisitor spikes, assuming they had not been completely hemalurgically decayed, probably couldn't create a proper hemalurgic construct, as they only had spikes with allomantic/feruchemical powers. The koloss definitely use strength spikes (iron) and the blessings are either copper, tin, zinc, or iron depending on which blessing it is (Cognitive function for copper/presence, zinc for emotional fortitude/stability, tin for senses/awareness). I don't think a hema construct can exist as we know them without one of these boosts. Also, trellium more than likely works more or less like atium and can steal physical/mental attributes as well as metalborn abilities.
I think nicrosil only gives you their abilities temporarily because it only gives investiture, meaning perhaps they burn that investiture keyed to those powers(?) I mostly say that because we now that tapping a nicrosilmind can give you non-metalborn powers like the Surges, given you are tapping that reserve. I don't think nicrosil would enhance existing powers, that would require a different spike. I feel like the metal types that steal allomantic/feruchemical attributes could possibly extend to stealing other magic systems, given the right circumstances. We know it can steal literally everything in the cosmere, just not specifically how of course.
