Those horns are thick and long for a female and that is a significant bulge.
Here are all the Tjj female pictures I have on hand most are mine some are from this site.
They all have different amounts of horn but in the females with 3 horns the paired horns tend to be thinner and/or shorter.
If he passes slugs let me know because as always with chameleons I'm still learning.
I like the younger male only because you will have more time with him and he looks like he is old enough to know his job. (Image begins with#62)
I assume you plan on breeding.
I would go by appetite on the females but you probably only have the pictures to decide. I'm partial to the green with the yellow stripe (imageB244) she looks less stressed but (image 5087) maybe younger. All of them look to be of breeding age and the females are all probably pregnant.
Single horned females can have 3 horned female offspring and vise versa so don't base you decision on that.