Males have very nice color & females not so much. I had a male fully colored up although not the tank boss. I couldn't find females for him & because females (that I saw) were dull - I didn't keep mine(had him 1 year). Aggression wise, mine was typical Mbuna; but not highly aggressive.
*** had mine for about a yr and a half and he is the tank boss and has been since the first day he was in the tank.He is not overly aggresive by any means but nobody messes with him.He always displays full color and is very active,great fish to have imop.
The Chewere is my fav fish! Beautiful colors and good temp. They are not overly aggressive but will be a top dog if not the top dog in your tank. I had a f1 pair back in the day i was maybe 15 or so. Now more than a decade removed from the hobby it was the drive to once again own a chewere that sparked my passion to get into the mbuna scene once again haha. I will forever own chewere's lol.
I have a group of 2m and 5f. Both males are colored up and definitely not the dominant fish in my tank. They finally just spawned last week but it looks like the female swallowed or spit the eggs. Hope they try again soon.