@CagerUmbonate This is just my opinion and I'm no expert, but here are the traits I would notice:
strong and prolonged focus on a subject (to the exclusion of all else) coupled with detailed knowledge of subject. A strength in my opinion
I know the person is there, but they appear to be somewhere else too
not bothering too much with social niceties - direct with speech
they want you to be direct with them, otherwise they don't understand what you're waffling on about and will get bored of you quickly. Other people frustrate them with inconsequential chatter. They might interrupt to shut them up and talk about something more meaningful
can get quite upset about (or fascinated with) what other people think are small, insignificant details. It may be a noise, a mark on a screen, an aroma, something wrong with dinner
they will tend to observe, rather than be the centre of a group, because they know they are outliers and they don't really trust the group anyway
sometimes though, they'll launch into a group discussion unexpectedly and may say something surprising or inappropriate (with no obvious context) so the group will feel confusion, want to ridicule them or even feel hostility
they're not really into you or your problems, which can make people think they're uncaring. It bores and frustrates them. They want you to like what they like.
they'll feel superior to others, because others say and do such stupid things. They won't understand the point of others. That's why they are often happy to go it alone.
OP, there's autism and ADHD in my family, but as I said, I'm no expert.