We don't even have a Xbox 1 (the first one) emulator yet. At the end of the day, you need to emulate an X86-64 CPU, the GPU, and the bastardized version of Windows running behind the scenes, all in software, on Windows.
I doubt it's ever happening, frankly. The complexity, plus the fact most every titles was released on the PC anyway, makes it likely no one is ever going to put forth the effort.