It will be revealed at E3 2016 and launched that same year, at least in Japan.
I also think that the Fusion part is about a common software platform between platforms, a same iOS and development tools.
And lastly, it won't be called HDS because the "DS" name has been overused but mostly because I think that it won't have 2 screens.
Please excuse my bad English.
Currently gaming on a PC with an i5-4670k@stock (for now), 16Gb RAM 1600 MHz and a GTX 1070
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