@Vid ,
I recommend using the new Ladybug Tools 1.0.0 that was just released last week. It has over 100 detailed HVAC templates and many of them are variations on the plant side of things, including swapping out boilers/chillers with ASHPs. Usually, when people say “air source heat pump” they are referring to something very different from a VRF. There’s also a big open question of what you are using to distribute the heat from the boiler or the ASHP (eg. are you circulating hot water generated by the boiler or ASHP through a baseboard system). Also, PTAC just refers to the AC and the heating with PTACs is usually done with a boiler and baseboard.
You can measure natural gas fuel energy in kWh; not sure what you’re asking here. You get multiple outputs for some of the detailed HVACs because there are multiple pieces of HVAC equipment consuming energy.