Is it possible for a DCGAN to do regression? What are some examples of this?
The answer is yes.  There is a paper Intra-class Variation Isolation in Conditional GANs (https://arxiv.org/pdf/1811.11296.pdf) discussing it.

They propose a "C-GAN that is able to learn realistic models with continuous, semantically meaningful input parameters".  They actually cover generating images of people at different ages as well.