Recently at a customer, that had around 20 Company Codes on their system, I faced a requirement where they asked me to perform their Intercompany config in Tcode OBYA for all the possible combinations / permutations between those 20 company codes.
Considering how this config works in the screen, it is hard to verify that you are not missing any combination and no relationship has been forgotten.
For that you would have no choice but to look directly into the Table in SE16N and do your analysis directly there.
To see this config, you will have to do SE16N on Table T001U – Clearing Between Company Codes
If your Company and/or Project needs to implement this or any of the functionalities described in my Blog, do not hesitate to reach out to me and I will be happy to provide you my services.