Where are you located?
Look locally first.
There are the Franciscan Missionaries for Africa, but they wear civies and a cross, no habit.
Missionary Sisters of Our Lady of Africa.
Perhaps some of the African congregations would permit you to join?
Blessed Mother Teresa’s Missionaries of Charity are international.
Be a chaste home missionary right now. Don’t ignore the poorest of the poor under your own nose. Are there any charitable organizations to which you could belong locally while you’re discerning. (This is along the lines of a nurse wanna-be becoming a Candy Striper).
Fr. Frank Pavone considers the poorest of the poor to be the unborn.
If you can’t be where you’re inspired to be, be there in spirit through prayer. I ask St. Daniel Comboni to pray for you.