What is the ruling on repeated oaths of divorce in different forms, intended as a threat and not to effect divorce, especially since the wife did not adhere to what the husband swore by?

If you did not utter the first pronouncement of divorce, and only wrote it without intending divorce, then divorce does not occur by it. And your saying to your wife, "If you pluck your eyebrows, I will divorce you," without the intention of divorce, does not effect divorce. And your message to her brother is not a divorce, but rather a warning and a threat. As for conditioning divorce on her going to her family's house while angry and applying makeup, if she violated you in these two matters, then two divorces have occurred, and she is irrevocably divorced from you by a major separation according to the majority of scholars. Some scholars, like Ibn Taymiyyah, are of the view that divorce does not occur by conditioning if divorce was not intended by it, and you are obligated to offer an expiation for breaking an oath. If you have divorced her as in paragraph 2, and she did what you conditioned her divorce upon verbally in paragraphs 3 and 6, then she is irrevocably divorced from you by a major separation and is not lawful for you until she marries another husband.