Question About Subclass Change Certificate

If I was to buy a scroll while they are available would I be able to change my male Kamael Berserker to an Arlbalester? Would I remain a male or change to female or is this not even possible?

Your character's gender will not change, only the subclass.

I just wonder why so many people keep asking if their character changes gender when subbing...

Because it says when you make your character that only female kamaels can be Arlbalesters.

Gender influences only the main class.

If you think logically about it, you can sub only 2 more classes (excluding Judicator, since it's a sub-only class). Depending on your main class, you can either sub Male/Female Soulbreaker (without any gender restriction, unlike the main class), Berserker and/or Arbalester.