The Airbox Runway HD/ACANS EFB app has X-plane mode. One conversation with a SIM engineer and he added some code that afternoon to our sim to output the right position stream onto the sim network...EFB connected to SIM network....voila! Fully operational EFB in the sim.
I think many EFB apps have probably already cracked the PC flight sim to EFB problem leaving you just the FFS to PC flight sim formatting problem. I think a fake GPS signal is nice but overcomplicated.