It was inevitable, I suppose; reposurgeon now has its own Emacs mode.
The most laborious task in the reposurgeon conversion of a large CVS or Subversion repository is editing the comment history. You want to do this for two reasons: (1) to massage multiline comments into the summary-line + continuation form that plays well with git log and gitk, and (2) lifting Subversion and CVS commit references from, e.g., ‘2345’ to [[SVN:2345]] so reposurgeon can recognize them unambiguously and turn them into action stamps.
In the new release 2.22, there’s a small Emacs mode with several functions that help semi-automate this process.