The Russian Federation is commonly known as Russia: everybody calls it Russia and nobody uses the acronym RF; China officially is “the People’s Republic of China” but all of us call it China, not PRC; Switzerland’s official name is Swiss Confederation and we call it simply Switzerland, not SC; Brazil officially is the Federative Republic of Brazil, who calls it FRB?
As you can see, the acronym of the name often is not used at all.
I also propose the simple name “European Federation”. Anyway, all of us know that everyone will always call it EUROPE (the best name of all)!