It looks like you’re searching for (the “Player” version or full “Kontakt” library) based on Reddit discussions.
– Get Vital (synth) , Spitfire Labs , or Decent Sampler (huge free library). Reddit backs all of these. kontakt vst free reddit
If you meant “free Kontakt libraries I can use with the free Kontakt Player” – the answer is almost none. Only NI’s “Komplete Start” and a few like “Arcane” (piano) work. It looks like you’re searching for (the “Player”