Sort of... You can bring a prop into the scene and replace a bodypart with it... so you could take the part of the model that you want to "graft" onto the main figure, and bring it into the scene as a prop (You may have to export it from the first model, then reimport it into the scene with your second figure), position and scale it so that it's where, and the size you want it... I'm not sitting in front of Poser, so I'm not sure exactly where it's at, but either someone here will know, or you can check the manual, but there's a menu somewhere that has an option for "replace body part with prop" or something to that effect... That's what you want... it'll replace the body part in question with the prop you select... now you can get into some weird joint issue when you pose the newly grafted body part, but sometimes it works out just fine... You can then save you hybrid figure to your figures library like you normally would...