They are playing on 1.0.6 so… After you select an opponent you should be getting a screen where your troops are on the left and on the right it says “To battle” just go to the troop you want to change (Probably with the joystick or whatever) and select it. Go to “Remove” After that a spot would be open, it should have a number from 1 to 4 just tap on it and a troop menu is gonna show, with all the troops you have, search for the one you want and just select it.
PS: “Remove” does not disenchant or make you loose the troop, it just remove it from your “battle party”
Edit 1: This is the screen you should be looking for:
I can’t post screenshot from the other steps because we no longer have the same interface… :sadface: