No, not really. This very question seems to come up every year, around this time, and the general consensus is that except during the spawning period ... they all look alike.
Females deposit eggs in several to many different beds. So you'd have to catch ALL the males or females off a spawning bank/area, before you run the risk of damaging the population potential (any more than what you're likely to do during the rest of the year). That's not very likely, on a body of water of any appreciable size ... since the spawn doesn't occur all at one time. It comes in waves, and runs over many days to several weeks, depending on weather & water levels/conditions. So, IMHO .... there's no real reason to target one sex over the other, so there's no real reason to be able to identify their sex, any time of the year.
There has been some studies that show a different shape of the anal opening can be used to distinguish between male & female Black Crappie ... but, the study & subsequent research paper published by John F. Smeltzer and Stephen A. Flickinger in 1980-81, was done during the spawning period, so it may or may not hold true during the rest of the year. Their consensus was that males had round or oval anal openings, females had teardrop or pear shaped anal openings.
.... cp