The moves come one day after starting cornerback Vontae Davis left the Colts' 19-13 overtime victory at Tennessee with a left knee injury. Interim coach Bruce Arians says Davis' MRI results were not yet available.
Moore had nine carries for 14 yards and four receptions for 36 yards and one TD in six games this season. Dixon made one tackle in two games.
Green and Hughes were cut in August and signed to Indy's practice squad in October. The speedy Williams was cut by Dallas in August.