The I-16 was the only radial engine plane that I know of that flew in combat between the "two big wars". I didn't count the Japanese fighters that flew combat missions in Korea and China prior to the declarations of war that started WWII since their engines were basically knock offs of American designs. In fact, one of their radial engines was an almost direct copy of the engine used in the Curtis P-36, the Wright 1820.
Give me a bit to find something for a quiz.