So I've got 2 faces.
I want the shinier head to the right to have the exact vertex positions as the other one.
I really need them to be on the object on the right without duplicate the left one.
I'd be really thankful if somebody could help!
If the models are from the same base (for instance sculpted one from the other, or simply modified a bit), so that they have the exact same topology, they can be mixed as shape keys:
To do that, select the mesh to transfer, then shift select the destination mesh. And in the properties panel, in the shape key part, use "join as shapes".
Now you have the left models incorporated as shape keys in the right model:
If you don't want to keep the shape key, simply slide the value to 1 and remove the shape keys (when removing, remove the others shape keys first and the one you want to keep last):
You can do this with my addon, Mesh Align Plus (assuming partially identical features). You would first match the scale of the source to the destination (with "Scale Match Edge"), then match the orientation (with "Align Planes"). GIF/summary below:
To match edge scale: under "Scale Match Edge", select two verts on your destination, hit grab, select two CORRESPONDING verts on your source, and hit apply to object. To match orientation, do the same with the "Align Planes" operator (select three verts on your destination, hit grab, select three CORRESPONDING verts on your source, and hit apply to object).
Selection order is important, by the way. And, you can also move the entire mesh while keeping its origin intact or just do it to a selection, but the steps are slightly different.