I've noticed in the Dossier Dialogue, Co-pilot's can be incorporated into the dialogue. I imagined I would find the option if I enabled Expanded Compartments, but haven't as of yet.

Am I just stupid and can't find the button to enable a co-pilot? Or is it just not implemented as of yet? (I am very much a Lancer beginner and don't know whether or not it just means AI co-pilots like WATCHDOG)

It seems to be AI copilots, yeah. Most NHPs from licenses also come with a preset appearance and dialogue personality (which I think you can edit). The NHP you get from TECHNOPHILE is fully customizable too.