Sally Hawkins very naked in The Shape of Water
This is Guillermo Del Toro's latest, which is considered by many to be a masterpiece. I haven't watched it yet, but I am a huge fan of Guillermo, so I'm looking forward to it. I feel that Pan's Labyrinth is one of the best movies ever made, and his genre films are always inspired and original.
This is the early front-runner for the best nude performance of 2018. Heck, it even got some support for the best nude performance of 2017, even though only a very few people had seen it (mostly at festivals).