I'm not your "go to guy" regarding Mbuna info, but I've kept a few over the years. Male Mbuna often display egg spots on their anal fin. The pictured Blue Zebra has the noted spots.
I unexpectedly received two male German Red Peacocks, and a male Cobalt Blue Zebra cichlid as a gift on Fathers Day. Surprisingly they are doing okay with my CA & S.A. Cichlids. Lol.