I didn’t add any custom bones, if that is what you mean. I just created a basic model with the program and then followed a tutorial that showed how to export the model from character creator and import it to unreal engine. I didn’t do anything to the bones manually, it was all done by the program by default. From what i can tell though, the bones are exactly like the UE third person mannequin, apart from the cc_base_jawroot bone which was assigned to “Custom_1” and there are quite a few other bones from the skeleton tree like eyes, neck, head etc, that are not assigned to anywhere in the retarget manager, at least from what i can tell. I also retargeted the third person character animations to my new model and they worked fine, except from the hair of course(i don’t know if this helps, i just thought to mention it just in case). Sorry i am kinda new to this.
Here are my import settings and i also used the cc_setup plugin. The UE version is 4.26.1