These Knights will be called Renegades. Their second name is also Grey Knights.

Added 5 minutes ago
Total number of these units: 5
Two armored knights, but with different equipment elements

Crossbowman

Paladin
Adept.
Visually, almost all are ready, except for one armored knight

In my opinion, the crosses don't quite fit... I understand that it's easier to draw, considering the symmetry of the texture for the shields of these models, but since you've already learned how to apply effects to the models, I suggest replacing their shields with asymmetrical ones... like here or here, or look at the NHF project; I retextured the standard shields of some of the Knights there, changing them from symmetrical textures to asymmetrical ones...
By the way, if the shield model of the armored knight with the Maltese cross (white eight-pointed cross on a black background) has an asymmetrical texture, then it would make sense to depict something heraldic and at the same time Renegade-like, but I can't quite see what that would be... what can be associated with Renegades and something visually cool, although... maybe a raven... a soaring raven