- Cameroon, Chad, the Central African Republic, Gabon and the French Congo are one country (No idea how you pull this one off. Maybe Cameroon and Gabon become one country and conquer their neighbors?)
Partial explanation (including Chad as well is pretty difficult):
1909-11 POD where Germany manages to get colonial compensations in Gabon from France (perhaps in exchange of a free French hand in Morocco).
In 1914 Germany invades Belgium, and Belgian colonial forces overrun the German possessions in West Africa.
In 1918 Belgium (possibly as a reward for the conduct of its troops on the Western front) is allowed to keep Gabon and is also given the administration of the conquered German territories.