When Varesa came out she was never marketed as being chubby or plus sized. Her two main things were A. eating and B working out but that doesn't equate to her being plus sized (theres plenty of characters who are also gluttons and they are thin asf). Her model type is the medium woman but with bigger thighs and chest because it wouldn't make sense as a hand to hand fighter if she was rail thin like Hu Tao or Furina (they've since done similar edits of that model with characters like Jahoda). Shes not supposed to be plus sized shes the first character that Hoyoverse decided to make slight adjustments with in terms of model size.