I don’t really use music notation software but rather DAWs, however if they can play using VSTs, I really like Noire from Native Instruments, the samples used are recorded from Nils Frahm’s own custom felt piano.

It’s not free (or even particularly cheap) but it’s popular enough I’m sure you can find it from not-so-legitimate sources if you knew where to look.

I don’t know any free felt pianos off the top of my head