How should this be understood? Well, everyone needs to share so that there is more diversity. Only then will Modding thrive.
No one answered me. Maybe they don't know, or maybe they don't want to share.
BUT!
I still found a person who suggested where I could find the game's mechanics (and their coefficients). In principle, it was logical that they were there, it's just that it's hard to find them in a pile of everything.
Well, let's thank him.

He suggested where the settings for secondary skills (and tertiary skills) are located.
Skills

And I accidentally came across the limiters for learning these skills in another folder. In the screenshot, they are labeled as "prerequisites".
Their limiters

This is how it looks as a whole:

Feel free to use it, those who didn't know :3