For the second year in a row, a Brazilian feature swept top honors at the annual Ibero-American awards event Premios Platino , dubbed the Platinos Xcaret after its venue in the Riviera Maya, Mexico this year. Kleber Mendonça’s “The Secret Agent” took home best feature, director, screenplay and actor ( Wagner Moura ) honors and in four other categories, topping last year’s “I’m Still Here” by Walter Salles, which won in three. The crime drama was nominated for four Oscars and snagged four prizes in Cannes, including director and actor.   Spain’s San Sebastian Golden Shell winner “Sundays” (“Los Domingos”) took home the audience prize, bestowed during a pre-awards ceremony the day before, where prizes to 21 categories, many of them newly introduced this year, were doled out.…