Angles and stance. Now I'm not saying they are or are not the same HRC, but look at the first pic, it's at a downward angle, lessoning the perception of HRC height difference between BC. If you also notice, he's dropping his right shoulder slightly, likely due to having his arm around HRC, or just behind her to avoid touching.

So the second pic, it's fairly face level with BC, increasing the perception of height difference with HRC, and his shoulders are squared.

So, while the pics themselves aren't a good source to use for height, if you look at (info taken from posts below), the 1st pic again, HRC appears taller, from Wikipedia: 2016 Hillary Clinton[48] 5 ft 5 in

In the 2nd pic she appears shorter: Teresa Barnwell 5'2" Source for this is unverifiable, in searching for her height 5'2 shows in the results page but doesn't appear in the article. Plus she's masked, the biggest "upon further inspection" differences look to be in her mouth, which would be easily "masked" by wearing a mask.

Angles and stance. Now I'm not saying they are or are not the same HRC, but look at the first pic, it's at a downward angle, lessoning the perception of HRC height difference between BC. If you also notice, he's dropping his right shoulder slightly, likely due to having his arm around HRC, or just behind her to avoid touching.

So the second pic, it's fairly face level with BC, increasing the perception of height difference with HRC, and his shoulders are squared.