Hi, can we assume that all the derivations rules and configuration needed to determine your partner profit centers are set? And all you want to do is substitute a different value base on the derived values? if so, then answer from Pankaj should point you in the right direction. If SAP is not automatically determining your partner profit centers based on the trading partners (trading company) then you need to do the initial configuration first for GL, AP, AR, Sales, etc.
You do this in the Profit center accounting and consolidation. Since I don't know what you have or don't have, start by searching "Partner profit center" in SPRO.
2ndly, for these derivations to work, you need to maintain the trading partner id in each of your master data areas like vendors, customers, gl. If you don't see the fields, then activate them in your field status groups and account groups for the respective master data. Now, after this, then when you post your intercompany, the trading partner will be used by SAP to cross populate the profit centers/partner profit center combo. Now if you need the partner profit centers to change based on some rule after this point, that is where your substitution rules come in.
Finally, all these would work in an orchestra fashion as long as the intercompany transactions are within same system and client. If you are looking at cross clients, then BADI becomes your best bet. That is part of the consolidation configuration as you will see. Of course there are many other ways to effect these derivations and coding block rules. Just revert back with clarifying questions.
Thanks,
Sam