All the renders are done using Daz Studio. Many of the character models are sold through Renderosity, and were created by an artist known as Sangriart. (His full store:
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) If you go there, you'll see that many of his/her characters are designed as look-alikes for well-known actors and actresses.
Essentially, these are all a combination of a head-and-body morph and custom materials for one of the Daz Studio Genesis characters (Genesis 3 Male, Genesis 8 Male, Genesis 3 Female or Genesis 8 Female).
How exactly Sangriart goes about modelling his/her characters is not known. There are any number of ways to do this. Zbrush is one common application used for this, although it's far from the only one.
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