Here "hand" refers to God's power, and raising the hand against them represents punishing them. AT: "because Yahweh of hosts has raised his powerful hand to punish them" (See: [[rc://en/ta/man/translate/figs-metonymy]] and [[rc://en/ta/man/translate/figs-metaphor]])
The "land of Judah" and "Egypt" refer to the people in those places. The Egyptians will stagger because they are afraid. AT: "The people of Judah will cause the Egyptians to stagger" or "The people of Judah will cause the Egyptians to be terribly afraid" (See: [[rc://en/ta/man/translate/figs-metonymy]])
Here, "them" and "they" refer to the Egyptians and "her" refers to the people of Judah. AT: "Whenever anyone reminds the Egyptians of the people of Judah, the Egyptians will be afraid"