Just a suggestion.
My son (who lives in UK but has property here) and I have a power of attorney for each of us, so we can transact just about anything for each other (in Spain).
An alternative way, for say just a bank account, would be to have an on-line banking facility set up and allow a trusted person to know the details. Then, as suggested, if the bank does not know that the account holder has died, all the cash can be drawn out or transferred.
Seems a bit hardhearted, but I have told my wife, that when I die, before she does anything else, empty our joint accounts.