Keep in mind that even OTL, in Palermo, until the end of the sixteenth century there was a portion of the Kalsa district, which was inhabited by Greek immigrants, who carried out the trade of fishermen, sailors and carpenters, so as to give their name to a city gate, the Gate of the Greeks
Community that also had an Orthodox church, dedicated to Saint Nicholas, which was destroyed in the anti-Bourbon revolt of 1848. In the photo, the little that remains
OTL the Greek community, for religious reasons, was treated badly by the Spaniards, much worse than the Orthodox of Piana degli Albanesi: at a certain point, with the excuse of modernizing the walls of Palermo, their houses were demolished without compensation. Following this and other harassments, the Greeks abandoned the city.
ITL being the Ottomans on average more tolerant than the Spaniards, the Greek community could also grow and reach today
