You need a T155/70R18 sized tire, a wheel (KT4Z1015A) which is sized 18" x 4", 5 Lug, 4.25" Bolt Pattern, and the jack with components. From the attached diagram, you only need the jack, mounting stud, wing nut and wrench so that it is secured in the well. The mini spare became an option around the 2021 model year. For some reason, Ford included the mini spare with some new Edges, but charged $100 (see the attached window sticker.) It was not included at all on others. I would search your local salvage yards for these items. Be careful that you find the 18-inch tire and wheel, not the 17-inch combination. Since the model refresh in 2015, these items have remained the same, so there should be plenty of availability.
windowsticker.pdf