Endpoints that handles transfers between accounts usually have a sender and a recipient account identified by parameters FromAccountKey and ToAccountKey. Some examples are the POST /v1/partner/cashtransfers and POST /cs/v2/cashmanagement/interaccounttransfers endpoints. In this context the parameter Currency refers to the currency of the recipient account. Such that if you are If you are transferring funds from a DKK account to a JPY account then "Currency" is to be set as "JPY".
You can use the endpoint GET /port/v1/accounts/{AccountKey} to lookup the currency of the recipient account by making a request with the ToAccountKey.
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