As someone who struggles with partial face-blindness - I can recognise people when I meet them, and I know what people look like, but if I try to visualise the face of someone who is not right there in front of me at the time, I find I can only visualise their face as individual features, and am unable to assemble those into a coherent face; it's a bit like alphabet soup, only with facial features - I am constantly fighting to make sure I don't get stuck in the same-face swamp.
The first example that sprang to mind from someone else is Junjou Romantica:
I know you won't believe me, but there are actually six different individual characters on that page, and not just colour-swapped repeats of the same guy over and over again.
But as I said, because of that partial face blindness, I push my own characters' faces into being as different from one another as I can manage:
