There's SH3 animations and SH4 animations.
SH3 is easiest to create and S3D can handle them in KeyFrame or MeshAnimations.
Here's the important stuff about SH4 animations.
https://www.subsim.com/radioroom/sho...d.php?t=207142
And SH3 animation stuff.
https://www.subsim.com/radioroom/sho...d.php?t=176928
It will list as Madox58. But that was actually me.