>>12724721Gallade is one of the only two psychic/fighting type pokemon with the other one being Medicham. Gallade is better in every way even regarding Medicham's Pure Power ability.
Gallade has 125 base attack compared to Medicham's 60, more than double in base Special Defense so that it can actually soak a special attack before a retaliation, and a better movepool because of the ralts line.
So Gallade may be a male-only pokemon but it also is a dawn stone evolution which is also for the female only Froslass. So in short, Gallade gives another option of use for a Ralts if their attack is good and you want a dual typing on your team that doesn't get KO'd by a dark type move every time.
Gardevoir can be male or female. It does well as a cleric role anyways and clerics are both genders so why not?