Ask first your company if you can apply sponsorship for your wife. If they allows you, then you can request NOC and Computer paper from your wife's company. If you have all the documents from your side( salary certificate, passport copy, marriage certificate attested by embassy and ministry of foreign affairs) and your wife documents,you can go to immigration and fill up the transfer form and pay QAR100. That is the time they will cancel your wife previous sponsorship. I am also transferring my sponsorship to my husband:))