In 1942, the AL All-Stars played a team of players who had entered military service but who had yet to go to the Atlantic or Pacific Theatres. There is information on that game in the 1943 Baseball Guide by the Sporting News (available on archive.org), as well as this picture of the team (you can click the photo to see it bigger, so that the names are more visible):

Among the players you can find in this photo are Bob Feller, Mickey Cochrane (who managed), Hank Gowdy (who was a coach) and a variety of other major leaguers such as Cecil Travis, George Earnshaw, Mickey Harris, Sam Chapman, Pat Mullin, Benny McCoy, and others.