Need to Map New Project Members to Existing Project Members Without Adding Them to Hierarchy

We have a requirement in our EPBCS application where certain new project codes coming from source data need to be mapped to existing project dimension members in the application.
The key point is:

We do not want to create these new project codes in the Project hierarchy.
Instead, during data load or processing, these new codes should be translated/mapped to the existing valid project members.

Please confirm the recommended approach to achieve this in EPBCS. Specifically:

Can this be handled through Data Integration (Data Management) dimension mappings
Is there an option to maintain a mapping table or explicit mappings so that source project codes are redirected to target project members without adding them to the hierarchy