The new export interface is now part of CiviCRM "core" as of version 5.23. In other words, this extension is now unsupported, since the feature is maintained as part of CiviCRM itself. Read more.
Since CiviCRM 5.x, extension releases compatible with CiviCRM 5.0 are compatible with 5.0 and later. An extension release compatible with 5.25, for example, means that it requires CiviCRM 5.25 or later.