WASHINGTON — Federal prosecutors announced criminal charges on Wednesday against six Volkswagen executives for their roles in the company’s emissions-cheating scandal, a sharp turn by a departing administration that is trying to remake its image of being soft on corporate crime.

The six executives include a former head of development of the Volkswagen brand and the head of engine development. One of those charged on Wednesday, Oliver Schmidt, was arrested in Florida last week; the other five are believed to be in Germany.

Volkswagen also formally pleaded guilty to charges of conspiracy to commit wire fraud and to violate the Clean Air Act, customs violations and obstruction of justice. Many of the 600,000 cars in the United States equipped with emissions-cheating software were imported from Germany or Mexico.

The automaker is set to pay $4.3 billion in criminal and civil penalties in connection with the federal investigation, bringing the total cost of the deception to Volkswagen in the United States, including settlements of suits by car owners, to $20 billion — one of the costliest corporate scandals in history.