At one inch, sometimes males will start to color up, but that's the exception more than the rule. And often the color is faint, not full adult color
Chances are, the fish is hormoned.
I will not recommend buying fish at Walmart.
But if you buy him anyhow.. keep in mind, female africans can get male colors from hormoning too.
There's a pet store here that buys hormoned fish, but it's generally a good store.
If I buy an peacock or hap there, I try to find one that's been in the store long enough for the hormones to fade.
With practice, you can spot an immature male, and eventually he will color back up naturally.
I only have bought a few of these for a display tank. I just assume that if they've been hormoned, there's probably reproductive damage, so no chance of using them as breeders.
Although maybe the males would be ok, who knows.. I wouldn't count on a female that has been fed testosterone though.