The OP should ask their CAA.
Under FAA rules you can log the 91(k) time and maybe the 135. While Terry is right that you have to be a required crewmember to log the time, 61.51(f)(2) says you can log the time if you are required by the regs the flight is operated under or by the type certificate. So if an insurance company requires a PC-12 F/O for part 91 flights you could not log that time. However 135.101 requires a F/O for passenger IFR flights. So the time flying pax IFR under 135 rules could be logged. However many operators get OPS SPECs paragraph A015 which allows single pilot IFR pax flights. So then you could not log the time. But if the autopilot is written up as inop and deferred the MEL may allow the flight if you have a qualified F/O and so you could log the time. Simple, isn't it.
Again, this applies to FAA logbooks. I have no idea what your CAA wants.