Wow. They are just sooo beatifull. Congrats.
As far as I can see ( you should actually take of all of them a picture from above to be quite certain) there is just one possible female. And I'm afraid it are only males. I will explain to you why.
The chance on a male or female is pretty much 50/50. The breeder of your fish is able to see which ones are females and which ones are males, with 90% certainty. ( only he can see because of grow rate. ) now he selects the males to sell and keeps the females.
Why? You think? Possible reasons are he needs females sothat he can have more nest make more money. He grows the females up to make a huge profit on them. ( because fullgrown females are very very expensive) or he doesnt want others to breed with them to keep the price high.
I'm srry for you if you wanted to breed with them. But these are the facts. Best you can do is grow these up and sell them sothat you make some profit and buy all young fish of a single nest sothat the breeder can't select themm.
I hope I helped you a bit.
Vince