Obadiah 9 warns that the mighty men of which place will be terrified?

Answer: Teman

"Your mighty men, O Teman, will be terrified," so that everyone in the mountains of Esau will be cut down.

“In that day, declares the LORD, will I not destroy the wise men of Edom and the men of understanding in the mountains of Esau? Then your mighty men, O Teman, will be terrified, so that everyone in the mountains of Esau will be cut down in the slaughter.”— Obadiah 1:8-9 (BSB)