Convert a skin texture (UV) from another game to The Sims 4

Hi. Bad choice for a first project. This is a tedious and time-consuming process
- in s4s main menu click on CAS, choose the first thing in the list for the fem frame, click Next, name it something, save somewhere;
- in the Mesh tab click on export, open in blender. You can have an easier time with this if you choose a lower lod instead but i cannot guarantee accuracy;
- delete the hat, expand the rig, make head_2 selectable;
- select it, in edit mode enable x-ray, click-and-drag to select half of the head;
- press Delete, choose Vertices;
- important: with uv_0 selected, create a new uv map with + and select it. If you forget this step, everything will have to be re-done;
- to be able to see the changes you make, click on the camera icon next to your new uv map;

- expand the timeline and switch it to the shader editor;
- select Material output and one Principled PSDF, press Ctrl I, then Delete. Connect the remaining ones;
- click-and-drag yellow socket from Base color into nowhere, type in Image, choose Image color;
- in the created node click on Open, choose your image;
- in the uv editor select everything with A, click on Browse and choose it as well;

- in the uv editor press S Y 2 to brings uvs to their original height. Choose Face select, select ears, move them away, move the back of the head away as well;

- in the uv editor, UV - Mirror - X, align with the texture;
- switch to uv_0, flip as well, align;
- enable the camera icon next to uv_0;
- switch to the Render tab, enable Cycles. Expand Bake, change to Diffuse, disable Direct and Indirect, Margin size to 6;
- duplicate an existing image node, create a new 1024X2048 image, change alpha to 0. Keep this node selected. Hit Bake;
- in the Uv editor click on Save as, save this image, close this blend

Alright ! Thank you so much, your guide was extremely detailed and it worked exactly how you expected. (I guess)

But I have a problem with your way of doing it, cause as I split the face in two, and start grabbing/relaxing only a half of the face, the UV map at the middle of the face doesn't follow a straight vertical line anymore cause the vertex points get separated from the other half of the face. Resulting in this pretty good but not perfect result when I merge the two images :



Zoom in :



But maybe I misunderstood one part of your guide. I'll have to "correct" this, so the two uv maps (UVMap, not uv_0) merge well at there junction, by displaying the right and left uv at the same time i guess, before baking.

But it was not that hard, thank's to you =)

IT IS DONE :D For the face tho. Now I have to do it for the rest of the body ! Thank you so much, it was hard to align the mirrored uv maps manually, I didn't find a way to do it in one click. But the result is pretty descent :

Those are the diffuse and normal textures. I hope I can use it to create more relief.