Hi, I have this problem, when I off focus my character for a particular shot, the eyelashes seem not blur and comes out with this outline. That also includes parts of the hair. 
Does anyone know how to fix this?
Thanks75% of original size (was 669x19) - Click to enlarge

Double click the CC Eyelashshader , type DOF into the search field and switch from "Before DOF" to " After DOF" , same for the "Hair shader" :

75% of original size (was 669x19) - Click to enlarge

Yeah I tried it. It didn't work. Is it because my models are Daz Genesis characters? 

Ohh , it is not the "Eyelashes Shader" but the "Occlusion Shader".
As long you are using CC Shaders there should be no difference.
Be sure to "save" the Master shaders after switching to "Before DOF" or "After DOF" or it will not be compiled.

Here is an older Tutorial in UE4 but it works in UE5 too.