currency conversion rule is not applicable when secondary ledger sharing the same currency

Summary:

We have a Primary ledger with currency EUR.

The Secondary Ledger currency EUR.

Our requirement is that foreign transactions created in Primary ledger should be converted in Secondary Ledger using different exchange rate type.

For example:

A journal in the primary ledger is created using CORP rate type.

When this journal is transferred to the Secondary ledger it should use the 'LOCAL' exchange rate type.

and this is required by local accounting standard

But because primary ledger currency and secondary ledger currency is the same, in secondary to primary ledger mapping setting, we can't setup currency conversion rule. Is there any way system can achieve this?