Unfortunately this is not a real camera, but it's a few thoughts about one. If you're interested, keep on reading and please leave a comment if you have one.
Let me start off by saying that while I think my Fujifilm cameras are great for their small size and lightness, small size is not always only great news. It depends on what they're used for. If I shoot street photography for example, obviously I want the camera to be as non intrusive as possible, and light to walk around with for hours, so then obviously having an attached battery grip is not the best and it will come off then. Also while travelling, size and weight is important, trust me, I know. For landscape shooting it could be either way, if hiking a lot, obviously size and weight matters as well and the smaller size is be good here. But since I mostly shoot models/portraits at the moment, the battery grip is at least for me essential for good ergonomics.
I had a short discussion with another photographer on Fuji X-Forum about camera body size and the thought about a "pro" sized body version of the X-T2 came up. And I totally support that idea. An X-T2 with a built in battery grip, with the same features as the battery grip has today, but integrated all in one piece, like Canon's 1DxII or Nikon's D5 but still just as big as the X-T2 with battery grip. It would open up for a larger and better battery, with more power or maybe even space for two of them. Since it's an integrated grip, a lot of room could be used, that aren't being used today because of the construction of the body and grip, so to speak.
This could attract "pro" photographers that not only like Vanessa Joy (see my last post) care about what looks professional, actually needs and wants the features, especially with use of longer lenses or when shooting lots in portrait mode. Sure, there's only 2 larger Fujinon lenses today, but there might come more with time.
I would buy this camera in an instance, and I don't think I'd be alone.
I don't think there will ever be one, but how awesome would it be? Sure, it wouldn't be as flexible as the X-T2 with an attached battery grip that can come on and off when needed to either save weight/size or when the features are needed. At the same time you would get an even sturdier design with an integrated grip, better ergonomics while shooting with big lenses or in portrait mode and the ability to have more power, something that is still a weakness of any power-hungry mirrorless camera.