I'm not too experienced in this cos I'm only just starting up P7. But you might want to do a google search for 'BVH Files' There are a few sites offering free downloads, one of them had a number of fight stances and animations. If they're not made specifically for Poser you will probably have to tweak the model's skeleton structure, but this may prove easier than animating from scratch. Hope you get a solution. Good luck.