I am trying sx sy sz in the Rename Scope slot but I have no idea what Attribute Scope should I match.

Basically, I would like to change the scale of boxes that are copied along a line and so the scale would change from bottom (small) to top (big) and reverse….in a vertical wave motion.

Is sx sy xz the right ones to use in this case? But I can't find the right scope to make the CHOP at least not errored out

Any idea? Or I am looking at wrong way?

I think copy stamping would be sufficient for this use case. As for CHOPs, it's really hard to tell how you're approaching it without a .hip file.