I just label him as teacher.
His disciples would still have called him "rabbi" though, even though it wasn't a formal title yet. It is important to remember that Jesus lived in that formative period of later Judaism that spawned the nuclei of rabbinic thought. He would have, and indeed did according to the gospel accounts, take part in the debates that eventually coalesced into the Talmud such as on the strict vs more liberal interpretation of divorce, as an example. Contemporary sources at the time of Jesus indicate that there was a relationship between a “talmid” (disciple) and his “rav” (master). The same word, “rav” had an “i” added to the end to mean “my,” in a personal sense, so that a disciple would address his teacher as rabbi, "my master" as the apostles are shown as doing in the gospels.
The formalized title of a "rabbi" in the period after the fall of the Temple grew out of this original, personalized attachment of disciples and schools to their "master".
So to his band of followers he definitely would have been, in my opinion, "rabbi".