I don't know if this is intentional or not, but currently KNP fades out all non-targeted enemies in combat, regardless of what fade options are set. Although there are options to prevent fading of low health enemies and friends, there is no option to keep all enemies unfaded.

So if the current behavior is intentional then I suggest to add an option to keep enemy nameplates from fading once one enemy is targeted.

Unfortunately the "Avoid tracked or in combat" option does not work with combat dolls.