All female wrasses are capable of turning into males, and female fairy wrasses readily do so.
Their pattern and coloring are similar to males. Males colors are more intense and pattern is a bit more intricate.
As the mystery is of the Pseudocheilinus genus, this could be problem. Wrasses of the Pseudocheilinus genus do not mix well with other wrasses.In my 180 gallon, I already have an established exquisite and a mystery wrasse. Both are about 3". Will it be okay to add a 3-4" female Labouti? I already lost a 2" yellowfin flasher wrasse since the two picked on it.
Anthias will also change without others present. It may take longer as they are suited for life with others of their own kind, but changing sex has to do with how much they are being kept female by displays and chasing by males. If they are not being "harassed" enough they will turn male.
I see your point. I see my male anthias and male fairy wrasse flashing or showing off in front of the females, and I often thought those quick moves they made were kind of aggressive. I guess what you're saying is those acts put the gender changing in submission. Without it, the female will turn into male naturally. Right?