Infraction: 1. All posters are to make an effort to communicate clearly.
Message to User:
Please use the shift key on your keyboard to make your posts more readable.
maybe it works if you just change the order of the macro to
#showtooltip Betrayer of Humanity
/equipslot 17 Betrayer of Humanity
/equipslot 16 Betrayer of Humanity
/cast Berserker Stance
Like this you first get your schild out and then equip BoH in main hand but i cant test it myself because i dont have 2 identical weapons.