Agents - Hide Faction?

I haven't been through every nano an agent has available to them, but how is it something like "False Faction" hasn't been given to agents? Like someone said in another post, "how can an agent gather intelligence if the guards are blasting him", but instead of "concealing" and having to walkaround "invisible" in a sense, why not just hide in plain sight?

It seems like it should be an obvious concept, though admittedly tricky to implement. If you can fool the nanos into thinking you are of a different profession, why not those of the opposite faction? It seems an agent would then become more useful for the tasks they might be called on to perform, or at least allow agents to slip into enemy cities without instantaneously being blasted. Is that not what an agent is supposed to do?