Is it permissible, in Islamic law, for a man to write a deed of sale to his wife for some of his properties, to become effective only after his death, in order to help her dispose of them freely without having to refer to the Guardianship Council, which would be the guardian of his minor children's assets?

It is not permissible to write over property to a husband in a manner that suspends the gifts upon death, because it takes the ruling of a will, and a will to an heir is forbidden, due to the saying of the Prophet, peace be upon him: "There is no will for an heir." However, if the property is written over and delivered to the husband during life, this is permissible, unless the intention is to deprive the heirs.