I agree with you about using modern day nation names being confusing, but just as a correction it would be the Adalite Empire at that time, and the King of Ifat, the precursor state to Adal, was the one who brought coffee to Yemen when he was in exile. Before that local sufis would chew the fried bean as a sort of trail mix, as they still do,

https://somalikitchen.typepad.com/my-blog/2014/03/fried-coff...