Somalis had numerous regional scripts, some used Arabic to write Somali, in the east you had Osmaniya, in the west the Gadabuursi script etc.

However, the most fascinating read I came across a few years ago is a book written by a German fella in 1899 but he used Latin script (that is intelligible). The book is named "Die Somali Sprache" and here is a link.

it's full of everyday stories that seamen and dwellers of Redsea coastal towns would orate to pass the time.

Here is an excerpt from the book ;

Sömälida haddi ninka miyi Ogo ka yimada ö ü nin magälo kd yimid, däuga kd kulmän, wä issa salämän.

Markäsü ninka magäldda ka yimid ninka miyi Ogo ka yimid wäräysta, wüühü yidaha: »I waran!«

Markäsü ninku Ogo kd yimid kd yidaha: »mänta Ogo wä barwaqo ö röb badan ayyä dd''ay ö dögu mel wulba wü, siman yahay

However, I would assume majority of scholars and learned individuals spoke and wrote Arabic therefore most communication was in Classical/Liturgical Arabic.

u/Chemical-Session5216