as far as my knowledge of genetics goes, no matter if the plant is hermie or not it can only pass off ONE sexual chromosome. So it's 50-50, same as with normal plants.
Well since a normal plant would produce a seed with a 50/50 chance of having either XX or XY chromosomes because one parent is female and one plant is male. Now, if your hermie plant started as female, that means the only possible chromosome for them to pass on to the buds they self-pollinate is the female XX. So that means a hermie plant that started as female will produce pollen bearing the XX chromosome to the buds, which also have the XX chromosome. Theoretically 100% female seeds? But those plants would probably have a greater chance of becoming hermaphrodites themselves. Someone correct me if I am wrong, I am far from an expert.... Just stoned.
I hope hermie seeds are all female.. my last grow went to the dogs when it decided that it wasnt happy with who it was... Now i have about 200 hermie seeds of a decent strain... If they are all female, then HOORAY!! If not, bah humbug.