I remember watching the Kings and Generals video on the Ethio-Awdal war, and in the video it was mentioned that the Portuguese helped in manufacturing Ethiopian made Muskets & canons during that war.
Not sure what source they used for this information, but I wonder if there's remnants of indigenously produced gunpowder weapons/cannons in the region.
In the video it's mentioned from 15:10 to 15:30