How can a girl be deterred from altering her God-given appearance, such as plucking eyebrows and defining lips, if one wishes to marry her?

A Muslim must regulate their behavior in a way that pleases Allah, so they should not associate with or establish any relationship unless permitted by the Sharia. Among the forbidden relationships is establishing a romantic relationship under the pretext of intending marriage, due to the impermissible speech, glances, and seclusion it involves. Whoever is afflicted by this must repent. As for that girl, you must instruct her family to compel her to abandon forbidden acts and to teach her the rulings of the religion. If she does not reform, then inform her through one of her female relatives that you will not marry her unless she returns to the religion and rectifies her affairs, for the Prophet, peace and blessings be upon him, said: "So win the one who is religious, and you will prosper."