GnusHardSort

If you prefer to view articles sorted by date, you may be annoyed that articles moved from another group will appear after the previously existing articles, even if the moved articles are older. You can always sort your view of the articles by date, but that may take a significant amount of time if there are a large number of articles in the group. In addition, your default view when you enter the summary buffer next time will continue to show the moved articles out of order. This function permanently resorts the articles in the group by date, by first sorting the articles, then respooling the articles back into the same group.

Lisp:gnus-hardsort.el