Hmm I’m no plant expert, so maybe I’m wrong about this but I thought fruit always grows after pollen moves to an egg like part of the flower/plant, so the ‘sex’ of the fruit is always a combined pollen+egg like cell. This cell develops into a seed while the surrounding plant grows the fruit for various reasons. Maybe there is a heterozygous genetic trait in some plants where we could label the individual as sex A or B, but I thought self pollinating plants were basically both sexes at the same time??? Idk… Maybe I should do some googling but heck the fediverse needs content :P