If I understood correctly from earlier posts in this thread, then the An-28 will be released as a separate mod. The interest was to him, so he proposed an addition. And if there is no An-28 at all, then it is impossible to put the config on it separately - for the early versions of your mod on the Net are available, with the An-28 in the archive, but without a record in the mod config.
POOK, in its time in the early versions of the mod of the 'Swedish armed forces' was present light An-14 "Clod", and in the versions of the bomber as well. The model was not without flaws - but in general, quite beautiful and functional. In the latest versions of the SFP mod, this device is not used - it is removed from the mod. Maybe it makes sense to ask the authors of SFP this plane for the An-28 mod? As a completely logical addition: the An-28 is the direct descendant of the An-14.