quick male/female sex question.

Is it true males show sex first? Or is it random?
I have 9 plants and 2 of em are showing sex, both males.

It's not "random". Just like it's not random that some seeds sprout before other, or some plants given the exact same light/water/nutes grow taller, bushier, faster or slower than others. Some are just superior genetically than others.. Anyways, depending on the strain and the conditions, your healthiest plant should show sex first..