AHCS - use of accounted amount in journal line

Summary: Is it possible to use the accounted amount of a transaction in AHCS that only has an entered amount in the data supplied into AHCS?

Content (required):

Example: In the input data there is a USD transaction for U$100, the functional currency of the ledger is NZD.

We would like to set up a contra entry to the US$100 in NZD, so we require the accounted amount of the initial transaction.

The accounted amounts are included in the subledger but we do not see anyway to access these through the journal line rules or formulas as these seem to only reference the input data fields.