looking at the situation, it really feels like rather than trying to find who's stronger, one should really be looking for who's weaker. Niger, Mali, Burkina Faso, and Guinea combined probably can't resist the rest of ECOWAS or even Nigeria alone given that they're already fighting off insurgents and militias and shit. but Nigeria's president is also very unpopular and a war might terminally destabilize his position, and the amount of troops proposed (25,000) doesn't seem enough to hold all of Niger especially if it descends into guerrilla warfare.