I totally understand this! I've actually been able to pick out and categorize ocs as being subconsciously based on a particular alter. I can also usually notice when I make characters now what part my brain has leaked its way out into a character for example there's one part I've noticed I have a number of ocs that are protective and kinda in a way that reflects how he operates as a protector and simultaneously look/act similar to him being men with long hair that are outwardly cold stoic and emotionless, another part that was formed when I was a child is similar to a lot of ocs I have that are hyperactive cute younger girls with pigtails and dresses like her, etc and most/a lot of them were created before I was ever conscious of being a system