I look at the bottom half of the gill plate (below the jaw line) where males will have very few spots while the females will have tons of them even solid patches in some cases.
I just caught this one of her "playing" with my loach. They rub against each other from time to time but never really go after one another... It is very strange to watch. My loach never tries to spur her though.
EBJDs are more poplular and therefore more inbred. You are gonna get some body malformations when that happens. Of course, I'm not an expert on EBJDs so it could stem from something else. But I have seen a ton of deformed EBJDs. There is a shortage of the gene pool in my area I suppose.