Moss, 31, batted .234 with 25 home runs last season. The A's now have traded their top three home-run hitters from last season: third baseman Josh Donaldson (29), first baseman-outfielder Moss (25) and outfielder Yoenis Cespedes (17).
Moss, one of six Oakland players to make the All-Star team last season, is coming off hip surgery. He batted .268 with 21 home runs in the first half and .173 with four home runs in the second half. He is eligible for salary arbitration and is expected to make about $7 million.
Wendle, 24, was not ranked by Baseball America as one of the Indians' top 10 prospects, but he was limited to 87 games last season because of a broken hamate bone. He batted .295 with 16 home runs at Class A in 2013 and .253 with eight home runs at double-A last season.
Yahoo Sports first reported the trade.