I could've sworn this was put in the GitLab before, glad it is now
By the way, if any of you need a quick fix for this, literally just add
addHook("PlayerSpawn", function(p) if p.mo.skin == "skinname" p.mo.state = S_PLAY_STND end end)
to your character's lua. It basically just makes the animation start upon player spawn by updating your state. Really shouldn't need to do this, but eh.