Transferes

How do I transfer or exchange products in direct trading other than these?


Air Transport
Cable TV
Construction
Electric Power
High Tech
Internet
Military Services
Officers
Services
Shows
Software
Soldiers
Sport
Telephone
Vacation

You cant. Not all products can be traded on the direct trading market.

..and i'm going to assume that the only way to exchange products between countries in one empires are just military hardware..

That is correct. Other goods have to be sold through direct sales even among countries in your empire.