No it won't, the fitment on the reverse is completely different to the Golf one shown like below (Golf left, Polo Right).
Even more confusing there are two types of airbags for the MK6 GTI, one for MFSW and one standard. You need to get it right otherwise you may have a hard time depressing the horn function.
When buying the airbag make sure it comes with the harness wire, otherwise you need to purchase that on top too.