Can people win at Diplomacy using a "Qin strategy?"
I have a hard time seeing this being successful.  The problem is that it doesn't mean much in the early game for England to be allied with Austria or Turkey.  So effectively you'd be playing EI versus FG, while Austria and Turkey teamed up on Russia.  The likely scenario is that the 2 v 2 battle doesn't go very far, and the 2 v 1 battle goes well, resulting in a stronger Austria and Turkey.  At that point, Turkey pretty much has to attack Austria or Italy, and either way doesn't seem to bode well for England.

In general, having an ally across the board is nice, but it isn't a replacement for having an ally that you can coordinate with directly, especially in the early game.  You'd need to look at it as more of a long-term alliance.  Perhaps as England you coordinate with Austria, Turkey, and Italy, but you start by getting Germany to help you take apart France quickly (with Italy's help), then activate your cross-board alliance to take out Germany.  It's debatable whether that really meets the criteria of a "Qin strategy" though.