Greek–Yugoslav confederation
Formed by either Greece or Serbia
Needed the two above and also Albania, Croatia, Bosnia and Herzegovina, Slovenia, Montenegro, Macedonia,and Bulgaria
The Greek-Yugoslav confederation was a political concept during World War II, sponsored by the United Kingdom and involving the Greek government-in-exile and the Yugoslav government-in-exile. The two governments signed an agreement pushing the proposal ahead, but it never got beyond the planning stage because of opposition from within the Greek and the Yugoslav governments, real world events, and the opposition of the Soviet Union. The proposal envisioned the creation of a confederation of Greece and Yugoslavia. (Copy and pasted from Wikipedia)
Also could make it exclusive to Balkan Fed. or sth idk
Sahel-Benin Union
Formed by:
Côte d'Ivoire
Niger
Burkina Faso
Togo
Benin
Needed all five above
IDK about the backstory
Thoughts?