mtrecorder and spirecorder, what are they?
Both of these plist files appear to be part of the iOS operating system, that have been left in OS X by accident due to the shared nature of their development.

The reason you are seeing errors in EtreCheck for these files is that the plist files are telling the launchd process to run executables that don't actually exist on Macs, but only on iOS devices. And even then perhaps only on devices that are used for development.

I think you are safe to remove both files (although I would keep a copy of them somewhere), firstly because they are failing to launch anyway, and secondly because only seem to relate to components of the iOS operating system.