While I think this is going to happen, it doesn't validate the sources for this rumor about a new Slaanesh being covered up with a new model release. Of course there are lots of options still if you wanted something a little more originally Slaanesh.
These are rumors, please add the adequate amount of salt.
Industry professionals say:
The biggest challenge has been to balance the new design to be uniquely Slaaneshi while not being too overtly adult or sexual in nature.
Model size is 6-7″ in height
Look for the standard digitigrade legs with the “backwards” joints to remain.
4 arms, large crustacean claws below, hands up top.
Multiple weapon options for the upper hands: blades, whips, etc…
Corset style torso armor, covering breasts.
Heavily decorated skin pierced with rings and jewelry, and scarification emblems.
Head is highly elongated with a humanlike face, yet sporting deamonic elements including multiple sets of horns, several tongue options, and sets of inhuman teeth.