This command will put you in control of the target character. Execute the same command again to stop controlling the character. As this doesn't take you out of control of your player's character, you will need to execute player.tc or otherwise your inputs will apply to both your player and the target you are controlling.
togglecontrolsdriven Target Command
The above command will toggle your inputs affecting your character. You will need to execute this command when controlling any other NPC as otherwise your inputs will be applied to both your player and the NPC you are controlling.
This command would put you in control of the NPC with ID ff0044532 (allowing you to move/control the NPC with your mouse and keyboard).