Is it permissible to give money to someone who acts on behalf of the recipient to fulfill the condition of mutual possession (taqabud) in a financial hawala between two countries with different currencies?

The agent's possession is equivalent to the principal's possession. Agency in currency exchange (sarf) is permissible according to the majority of jurists. The majority of jurists hold that agency for taking possession in currency exchange is valid. So, if the two parties exchanging currency appoint an agent to take possession on their behalf, or if one of them appoints an agent to take possession on his behalf, and the two agents take possession, or one of the exchanging parties and the other's agent take possession, before the principals separate, or before the principal and the second contracting party who did not appoint an agent separate, then the contract is permissible and the possession is valid. However, a condition for this is that the taking of possession must not be delayed after the contracting parties separate. If the transfer is completed in such a way that possession is delayed for days, then it leads to riba an-nasi'ah (interest due to delay).