Is it permissible for a niqab-wearing fiancée to sit with her fiancé during visits in the presence of her family while remaining in her niqab? And is it the fiancé's right to see the face of his niqab-wearing fiancée during the engagement period?

The engagement is merely a promise of marriage. It does not permit the suitor anything except looking at the fiancée. He remains a stranger to her until the legal marriage contract is concluded. It is permissible for the suitor to visit the fiancée in her home without seclusion, and to speak with her on the phone when necessary and free from suspicion. However, speaking without need is impermissible because it is a cause of fitna (temptation/strife). The fatwa (religious edict) states the obligation for the fiancée to cover her face from the suitor. There is a disagreement among scholars regarding the permissibility of uncovering the face, and if it is permissible to uncover it, there is a disagreement regarding the suitor's permission to look at her. Getting to know the fiancée should be done by asking trustworthy individuals, not by frequent visits, excessive talking, and looking.