There's always more to be said on the topic, but I've written about cross-cultural contact in the Bronze Age in a few past posts.

• Egyptian-Hittite relations

• Hittite-Mycenaean relations

• Babylonian-Egyptian relations

• Hittite-Babylonian relations

• Hittite-Mittanian relations

I also touched on foreign relations in a few other threads:

• To what degree were Pantheons shared in the Late Bronze Age Near East?

• In the Ancient world, were kingdoms/Empires/Realm aware of events happening in far away places in other kingdoms/Empires/Realms?

• If the Amarna Letters were discovered in Egypt, why are their correspondences written by the Pharaohs and their officials and not just a collection of correspondences from foreign rulers?

• The biblical Hagar is described as Egyptian and working for a Hebrew family. Are there any records from pre-Achaemenid Egypt of ethnic Egyptians living and working outside of Egypt for foreign peoples?

Further reading

• Brotherhood of Kings: How International Relations Shaped the Ancient Near East by Amanda Podany – This is an excellent overview of the complex trade networks and diplomatic relationships between Near Eastern polities. Podany not only covers the Amarna letters and diplomacy in the Late Bronze Age but also the Old Babylonian period (the era of Hammurabi) and the Mari letters, the Old Assyrian trade colonies in Anatolia, and so on.

• Letters of the Great Kings of the Ancient Near East by Trevor Bryce – This is similar in content to Podany's book, but Bryce focuses on the Late Bronze Age specifically, particularly the role of the Hittites in Late Bronze Age diplomacy. Since Podany's book ends in the Amarna period (ca. 1350-1330 BCE) and does not cover the Egyptian-Hittite relations of the Ramesside period, this focus on the Hittites is helpful.

• International Relations in the Ancient Near East by Mario Liverani – This is a very dry but important book, and Liverani has influenced how every ancient historian analyzes the Late Bronze Age. Rather than write a history of kings and trade goods, Liverani focuses on the ideology and realpolitik of Bronze Age diplomacy, which makes it a very nice companion volume to Podany's book. You may want to check to see if it's been translated into your native tongue.

• Amarna Diplomacy: The Beginnings of International Relations edited by Raymond Cohen and Raymond Westbrook – This is a very unusual book in ancient Near Eastern studies, since it includes contributions not only by Egyptologists and ancient Near Eastern historians but also specialists in political science and international relations.