WI - Ethiopia retains Eritrea?

Let's say Operation Red Star is an overwhelming success and the Eritrean People's Liberation Front is either wiped out to a man or severely weakened to the point where they're no longer capable of offering any effective resistance to Ethiopia. What could this mean for Ethiopia? What effects would there be in both Eritrea and Ethiopia?
 
Eritrea would still remain warzone or at least there would be still much of terrrorism. I doubt that even that anymore helps if Ethiopia restores autonomy.
 
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