Do you think I'd be doxxing myself if I traced one of my self-photos and used that tracing as my profile picture?

It should be fine. I use my legal name and a broadcast picture for my account and never had an issue

I'd just use a pic of Karl Marx with sunglasses on but maybe that's just me.

I recommend keeping clean separation between personal details and online accounts. Even if this particular thing is a low-medium resolution tracing of a silhouette, because the lines would now be a little blurred, you might forget one day and use it for an account somewhere else that does have personal details on it.

I wouldn't do it.

I don't think so but I'm not the absolute best with opsec tbh

Some of these tiktok mfers can find someone with what seems like nothing

Assuming you mean a profile silhouette, it's not enough information by itself to know who you are, but someone could definitely use it to narrow down details about you. And if someone already has you narrowed down to like 10 possible people, they could definitely use a profile silhouette to single out which one is you.

What, like a silhouette?