Data Forms to input data for cashflow reports

Summary:

As we are working on the cash flow implementation, I have couple of questions as below -
We have a large number of entities (around 450+). When data is loaded into FCCS, each account is mapped to a single movement member as we load periodic data and this is the mapping setup. However, for debt and fixed assets, the team would like to reclass activity across multiple movement members as it depends on type of transaction.
We are creating a form to support this, but the challenge is that users cannot realistically perform reclassifications across all 450 entities. We were thinking of below options -