The 2002 D penny on the left, looks puffy compared to the regular 2002 penny on the right. Is there even such a thing as a doubled die cheek?
I don't think either of them has enough wear to make a difference . But as Kentucky has said these zincoid coins have a way of blistering .
I believe the coin on the left is more weakly struck. Notice the weaker jaw line. The bowtie is also stronger on the right. The right coin would be called a strong or fully struck coin.