Syli nationale first take on Cape Verde on Saturday 10 October before a game against Gambia three days later. Both matches will be played at the Estádio Municipal de Albufeira in Faro.
Julian has earned five caps since making his debut in the build-up to last summer's Africa Cup of Nations finals, being named in the matchday squad on a further four occasions.
The 28-year-old is currently on loan with Turkish Süper Lig side Kasımpaşa S.K. He has played three games since moving to Istanbul including Sunday's 1-0 victory over Galatasaray.