Can enemies get crippled/debuffed?

[Junknown]

Npc’s can be affected by everything that can affect the player. Monsters on the other hand are tireless, indefatigable, fearless*, feel no pain and are represented with a single health bar with no anatomy whatsoever.

That means the first thing on your list is possible while everything else isn’t.
For a more in depth answer see the frequently made suggestions thread, which has a section dedicated to this kind of question:

@kevin.granade

Monsters

1. Separate limbs for monsters: not useful
   The suggestion is usually along the lines of, “add limbs to monsters so they can be crippled”. The problem with this approach is you can add crippling attacks much more easily by just applying a crippling effect to the monster, there’s no need to track per-limb HP for monsters to make it happen. Also, a limb system for monsters would be much more complicated than the one for players, since monsters have a more variable number of limbs, so we couldn’t even just use the code from the player-based system.
2. Targeted attacks on monster body parts: not useful
   A similar suggestion is to allow the player to target specific monster body parts in order to achieve specific effects such as stunning with headshots or slowing by hitting the legs. A much simpler system is to have the player declare the effect they want rather than something indirect like targeting a limb, then we can be more flexible about how the attack plays out based on the combination of player abilities, weapon used, and monster type.
   For a better outline on what we DO want to do, see https://github.com/CleverRaven/Cataclysm-DDA/issues/1565

* Not true for all monsters, notably Mi-Gos know true fear.