All classes that implement OutboundPathProcessorInterface

class \Drupal\Core\PathProcessor\PathProcessorAlias implements InboundPathProcessorInterface, OutboundPathProcessorInterface
class \Drupal\Core\PathProcessor\PathProcessorFront implements InboundPathProcessorInterface, OutboundPathProcessorInterface
class \Drupal\Core\PathProcessor\PathProcessorManager implements InboundPathProcessorInterface, OutboundPathProcessorInterface
class \Drupal\language\HttpKernel\PathProcessorLanguage implements InboundPathProcessorInterface, OutboundPathProcessorInterface
class \Drupal\url_alter_test\PathProcessorTest implements InboundPathProcessorInterface, OutboundPathProcessorInterface