1) You need the pose player (a mod) AND the specific packages to use with the pose player to do that.
For the ones in CAS, it's generally an override of something in it.
For example, when you add the trait "Genius" to a sim in CAS, he's doing a specific pose/movement, so for the screenshots you can see sometimes in CAS, it's a mod that's replacing the default movement the sim is doing when selecting the trait (i don't know if i'm clear ^^).
2) What you want to do if i understood correctly, is that you want for example a stripper who would be constantly dancing on the pole, like if it would repeat endlessly the pose animation, that's right ?
Maybe it exists but it might be rare and/or very "specialized", so... check the stripclubs on LL, to see if someone integrated such a thing in his lot, that's generally how i find such things.