For node snapshot, it basically a post processing of .qraw datafile. In the forum, there are two projects to use programming software for post processing data and you can refer to this post. You can do whatever post processing currently Qspice waveform viewer cannot offer.
Where can i find the netlist and logfile - QSPICE - Qorvo Tech Forum
OR, there is a trick for this
In waveform viewer, File > Export Data…
Set as following to export a CSV at time you need. But currently I have to manually click each node to add into export expression.
