To what extent is it permissible for the wife's father to impose an order upon her that contradicts the husband's order? And can the husband take his wife to live with him in another country despite her parents' refusal?

A Muslim is required to fulfill his promise, but the statement "God willing, I will live there" is not a firm promise, so you are not obligated to live in Denmark if you do not see a benefit. If a woman does not stipulate in the marriage contract that she will remain in her country, then she must go with her husband wherever he goes, as long as the place is safe. Her father has no right to prevent her from doing so. It is permissible for a husband to travel with his wife, unless the travel is dangerous or she stipulated to remain in her country.