Welcome, Norman, to the OEM forum.
There are now two versions of emonLib, the original ‘discrete sample’ (DS) emonLib, and the newer continuous monitoring version EmonLibCM. The difference is the DS version records a sample of voltage and current normally lasting 100 - 200 ms (but definable) essentially when you tell it to, whereas the CM version records continuously and reports regularly at defined intervals - normally every 10 s.
I think either version will suit your purpose, because mains power is available. (We discourage the use of emonLibCM if the power source is batteries, as the power demand is continuous.)
I suggest downloading emonLibCM from the forum here https://community.openenergymonitor.org/t/emonlibcm-version-2-2-2/
There’s comprehensive documentation and some example sketches - these assume the data is going somewhere to be recorded so you’ll need to handle that according to what you have available in your existing kit.
(Your choice of IDE shouldn’t make a difference to emonLib or emonLibCM.)