BERLIN—Adidas AG plans to close its only sneaker factories in the U.S. and Germany, shifting cutting-edge automated footwear production to Asia and reversing an effort to make products closer to shoppers in the West.

The German company, the world’s second-largest athletic gear maker by revenue after Nike Inc., said Monday it would move technology developed at its so-called “Speedfactories” to two suppliers in Vietnam and China.

The...