Personally I think that Vin would win because of her access to raw investiture via the connection to preservation and his powers although if she had her earing in I think that would be an Immediate fail for her because that totally blocks her connection to preservation's powers but with Hoid's abilities of Yolish Lightweaving, Mistborn, Awakener, Lightweaving (Surgebinding), Soulcasting, Shardbearer, Elantrian, Worldhoping, Dawnshard holder (formerly), Ability to be immune to shardblades and others but the reason I think Hoid would lose is because even though Hoid has the ability because of the Dawnshard he held he is physically incapable of hurting people.