Is there any replacer ( not Taina's) that allow you to import your models to the game even if you change the number of vertex?
What type of model? Item or creature?
For heads you can't use anything else than taina's replacer tool. By using mdlops all head and face animations will be destroyed.
For anything else (body, items,) you can use mdlops.
Also, if the creature which you want to edit has mask_hook and google_hook you can attach headgears to cover head and add whatever you want (add tails, hors, big ears and stuff like that).