Is it permissible for a husband to order his wife to relinquish her legitimate right to inheritance in exchange for a sum of money, knowing that she is unaware of his wealth, under the pretext of guaranteeing her rights and the rights of his children from his first wife?

It is not permissible for a husband to command his wife to relinquish her inheritance from him, and such a relinquishment is not valid even if it occurs with the agreement of the people of knowledge. The husband must be content with what Allah has legislated concerning the laws of inheritance, because transgressing these boundaries is considered an act of disobedience to Allah and His Messenger, and a cause for entering the Fire, whereas obedience to Allah and His Messenger is a cause for entering the Gardens. Thus, whoever deprives an heir of their inheritance has transgressed the bounds of Allah and committed a grave sin.