.. if you get a debit card from Schwab Bank you can use atms without a fee. That can save you 5% of all the money you spend here.
I believe one must be a legal US resident to open a Charles Schwab checking account and it is necessary to open a Schwab brokerage account to do that. Nonetheless, I don't think you have to be a US resident to open the brokerage account.
If you can send money from Korea to an Argentine bank account using Transferwise you won´t pay ATM fees in Argentina as long as you withdraw funds from the same bank as your account (regardless of the sucursal).
And with an Argentine debit card you will be able to access your funds pesos at no charge at many businesses including major grocery stores and YPF gas stations when you make a small purchase.
PS: If you use Transferwise you won't have to change your dollars to pesos in Argentina. That will happen during the transfer.