When there's a damsel in distress, Mr Ogre man comes to the rescue!
To delete an animation,
Portrait sounds are just awfully bugged. But the solution is easy in your case, seeing that most faces haven't gone through a lot of cosmetic surgery: In Retera Model Studio,
right click on the model and you'll see the model, the model_portrait and, if I remember correctly, an extract option. Click on the
model_portrait, delete the skeleton and the organs since they just take extra space, delete whatever you are sure that is not going to show in the portrait for the same reason (legs, hands, the hip...) and, then, import the helmets and the stuff of your original model. Save it as whitestone_swordsman_portrait.mdx, for example, and you're good to go.
Now, import both in World Editor and test them. It's REALLY important to add the suffix _portrait at the end of the portrait model, and that both models share the same name.
Glad I could help. Welcome to Reforged Modelling!