They would have probably win but not that easily. Smoker already got stomped in canon(likely because of his physical condition though). Judging by Luffy's current pitful performance, he would have been easily subdued. Sanji wouldn't have brought up a lot to the table either judging by what happened during this arc and anyone below aren't worth discussing. Infact without knowledge, Doflamingo would have likely won if anything. But Law is there with his knowledge and the hax of his Devil Fruit. I think he would have been the key of their probable victory