Binary package “kde-config-mailtransport” in ubuntu focal

mail transport service KCM

 Mailtransport is a library that provides the following functionality:
 .
  * Shared mail transport settings.
  * GUI elements to configure mail transport settings.
  * Job classes for mail sending.
 .
 This package also contains a KDE control module which can be embedded
 into your application to provide mail transport configuration.