Is it permissible for a man who has committed adultery multiple times with a married woman to marry her legitimate daughter from another man?

The phrase "disagreement among scholars is a mercy" is not a prophetic hadith (definition). Rather, it has been mentioned in the words of some scholars, such as Ibn Qudamah, who believed that their agreement is a conclusive proof, and their disagreement is a vast mercy. Among the manifestations of this mercy is the ease and convenience that results from it, such as adopting a particular fatwa (definition) for a legitimate interest, like Ibn Taymiyyah's fatwa regarding three divorces pronounced with a single utterance. Ibn al-Arabi said that the disagreement among scholars is a mercy and a breadth for the creation. Nevertheless, it is preferable to avoid scholarly disagreements to distance oneself from doubts.