Is it permissible to give zakat to an undeserving Islamic charity that pays out the zakat immediately upon receiving the money, and in the event of the giver's death, pays the zakat immediately? And if permissible, does the giver benefit from the works of this charity? And is permission required when paying zakat?

Zakat (definition) becomes immediately obligatory once wealth reaches the nisab (definition) (minimum threshold) and a full hawl (lunar year) has passed. It is not permissible to delay it except for a slight, legitimate excuse. It is permissible to appoint a trustworthy person or organization to disburse Zakat, but such an entity is not permitted to invest Zakat funds in charitable or commercial projects. This is because doing so could expose the funds to loss or delay. Zakat must be disbursed immediately to its eight deserving categories mentioned in the Quran. Building mosques, schools, hospitals, or digging wells are not among the permissible expenditures for Zakat.