Hi!😃Domesticated Cacatuodies are a notoriously hard apistogramma species to sex when you. In recent years, females have been selectively bred for male characteristics, something no other apistogramma species has been subjected to so diligently. As previously stated by Auballagh and Mr. Chromedome most apistos are polygamous and cactuodies especially so. Many keep upwards of 5 females for each male, but a pair should be fine. Just be wary of any aggression.
For me to ID them fully, the fish would need to be at least a few months older. I would say you have 2 young males now given the fin extensions on the lower fish and the colouration on the first fish. However, the first could also be a female, as it is hard to differentiate at this age with domesticated cacatuoides.