Hollywood studios is just a different park with no real theme at this point.The piston peak, natural park, that they are trying to achieve would most definitely not fit the theme of Dhs.
With its recent additions of independent lands such as Star Wars, Toy Story, and soon Monsters, I could see a 4th land working well on the other side of the park and could bring balance. The approach could be similar to Epic Universe.
With that said I think it can work well in MK too. I would prefer that they don’t touch the river though.