What is the ruling on a mother forcing her divorced daughter to sell her share of her father's inheritance to her brother, while threatening her with displeasure, and what if the mother dies while displeased?

Obeying one's parents is only obligatory in what is permissible and good (ma'ruf), and forcing a daughter to sell her house is not part of that. Therefore, there is no sin upon her for refusing to sell, even if this leads to her mother's displeasure, while still being obligated to honor her and treat her kindly.