I believe we can make a case for missions in the Old Testament. In fact, God’s plan from the beginning was to bring salvation and redemption from the Jews to the world, which in my opinion is the “ultimate mission”.
From Abraham being called out from God and told that “all people’s on earth will be blessed through him”, to Isaiah receiving word from God about a King who’s come to redeem the Jews and gentiles. We can see that a world mission was the plan to begin with. Even the Jews felt this way about the rest of the world. Pg 34 gives us an example of psalm 67 where the Jews were longing for all people and all nations to know and see the goodness of God.