My new kipi-plugin to edit metadata is now completed.
Exif and IPTC metadata can be edited from scratch. Of course this plugin is based on Exiv2 library.At this url, you can see all editor dialog tabs. This plugin will be available on next stable kipi-plugins release. This plugin do not support yet XMP. In fact when Exiv2 wil support this metadata format, i will update the plugin.Also, actually only JPEG file can be edited. PNG, TIFF and RAW files will be supported in writting mode at next Exiv2 release.