How to restrict access only to specific project organisation using custom role in oracle fusion

The goal is to adjust the security settings for the Project Accountant role. Currently, access is granted at the Business Unit (BU) level, meaning the accountant can see data across the entire BU. The proposal is to reconfigure the security model so that access is restricted only to the specific Expenditure Organization instead of the whole BU. This will ensure more controlled and limited access to financial data.