Here "you" refers to Mount Seir, but the message is for the people of Edom. The abstract noun "desolation" can be stated as an adjective. AT: "Because of what your people did I will make you desolate" (See: [[rc://en/ta/man/translate/figs-personification]] and [[rc://en/ta/man/translate/figs-abstractnouns]])
Here "earth" represents the people of the earth. The word "entire" is a generalization that refers only to people near Mount Seir. AT: "people who know that I have destroyed you rejoice" (See: [[rc://en/ta/man/translate/figs-metonymy]])
This speaks of the land that Yahweh gave to the Israelites as their inheritance. AT: "As you rejoiced when I made the land of the Israelites desolate" (See: [[rc://en/ta/man/translate/figs-metaphor]])
Possible meanings are 1) I will make your land desolate" or 2) "I will rejoice when your land is desolate" or 3) "I will make other people rejoice because of your desolation."
# You will become a desolation, Mount Seir, and all of Edom
Yahweh continues telling Ezekiel to speak to Mount Seir as if it could hear him. The message is for the people of Edom. AT: "I will make you, Mount Seir, and all of Edom desolate" (See: [[rc://en/ta/man/translate/figs-personification]])
# Then they will know
The word "they" possibly refers to 1) "the people of the earth" or 2) "the people of Israel and Judah."