Is it permissible to give a small amount of money, specifically designated for a deceased woman, as charity, or should it be given to her children who are not in need, and how can it be delivered to them given their dispersal?

Everything the woman left behind belongs to her heirs, and no one is allowed to dispose of it except with their permission. What she left behind must be handed over to her heirs. If they authorize giving charity on her behalf, there is no objection, provided they are mature and adult.