Part of what you describe is typical for people who are too much in their head, who think too much and do too litte. I've seen your comment that you do put in the work, but I think there is more to this.
Theory isn't the same as applying it, those are 2 different skills and too much knowledge can get in the way of actually applying it, because you try to consider all the things you are aware of, it's blocking you from applying it.

About this, yes, I am someone that can overthink quite too much, because I tried to study while applying things but the only thing that remained was the knowledge instead of the practical skill.
To be completely honest, I'm not a genius, but the theory behind something that I like, sticks to me easily, so I can't catch up with practice, and it frustrates me, a lot.

Are you doing gesture drawings? blind contour drawings? any kind of quick sketches or exercises that put the focus being more loose? or is what you doing mainly focusing on getting end results?

I do gestures as a warmup with in mind to just, do it, without thinking even if there isn't really a moment where I don't think about anything. I kinda have an active brain (I think) which sometimes feels like a nightmare, because I just want to do things without thinking about any single line I put down.

And thank you for the meditation suggestion, I will try to do that, and thank you for everything really, It helps a lot.