You can let your relative open an Australian-dollar account in the Bank Of China and ask the Bank Of China to provide the account name, account number and SWIFT CODE. You can directly transfer Australia dollar to that account from any bank in Australia to that account. the fee is about AU$30. 现汇 is higher than 现钞,
国内取款时按现汇买入价 because you sell 现汇 to the bank.