Poser - OFFICIAL F.A.Q (Last Updated: 2021 Sep 26 11:30 am)
Yes, you can save it to your library. It gives you the option of saving just the figure or the whole group. If you choose whole group, the clothing, hair, etc. will be saved with it (as long as it's conformed or parented to the figure).
You can also save the Poser file containing the dressed figure, then open a new file and import the saved file as many times as needed. This will import everything, even things that aren't parented. (It will also import the lights, so you'll have to delete those.)
If you’re looking to have multiple instances in the same scene, with the figure selected, you can go to edit>duplicate and make copies. It will include anything conformed or parented. And it doesn’t make your runtime bigger.