There is a bug in the implementation of the vanilla horse animations such that any non-vanilla horses, (such as Creation Club or modded horse types) are unable to use non-default sounds.
The attached fix includes updated horse havok files and updated footstep animation tags. These allow vanilla and non-vanilla horses, (like the Dwemer horse in Forgotten Seasons, or the Reindeer in the Saturalia Pack) to use custom sounds.
The way this fix works is animation files have a list of tags associated with different animations. By default, the tags in the CK don't match the tags in the animation files, (vanilla horse sounds seem to be baked in a slightly different way). However, this means any non-vanilla horse attempting to set a different sound to be associated with the animation tags vanilla horses use won't produce any sound. This fix updates the animation files to use the correct tags, (from the tag list in horsebehavior.hxk), and the ESP file points the footstep sounds to the new, corrected tags. This allows both vanilla and custom horses to play sounds as expected, (tested and confirmed with the Dwemer and reindeer horse variants, as well as vanilla horses).
Attached Files:
Horse Fix.zip
Issue Data
Issue #29343: Horse Animations Fail to Play Sound for non-vanilla horses