Is it permissible to name a newborn before its birth, such that the parents name it "Khalid" if it is male and "Yasmeen" if it is female, and is there any sin in that?

The Sunnah is to name the newborn on their seventh day, as mentioned in the Hadith: "Every child is mortgaged by their aqiqah, which is slaughtered for them on their seventh day, and their head is shaved, and they are named." It is permissible to name the child before the seventh day and after birth, as the Prophet, peace and blessings be upon him, did with his son Ibrahim and Abdullah ibn Abi Talhah. As for naming the newborn before their birth, it is not recommended because it is a name for someone non-existent, even though there is no prohibition or sin on the one who does it. The preferable approach is to follow the Sunnah.