https://sims4studio.com/thread/243/sim-body-texture-templates
These are full size so you can just copy them and add them as a new image in your 2D editor, and if you want, there are also .png versions of the image you may download.
Uv map placed over body template, regular size (1024x2048).
Female UV
Male UV
Child UV
Toddler UV
UV map placed over body template HQ size (2048x4096). HQ size recommended only for people who know how to create files for HQ game settings. All pictures given as links since files are very big.