Is it considered Haram for a husband to curse his wife using her parents, even if the husband knows that she does not get angry, believing it to be a joke?

It is not permissible to insult the wife's parents or anyone else, even jokingly or with their consent. The Prophet, peace and blessings be upon him, said: "The believer is not one who curses much, nor one who is obscene, nor one who is shameless." He also said: "Nothing is heavier in the Mizan (scale) of a believer on the Day of Resurrection than good character. Indeed, Allah detests the obscene and the shameless." And "A Muslim is one from whose tongue and hand the Muslims are safe," and "Insulting a Muslim is wickedness, and fighting him is disbelief."