Hi @Jocelyn,
Transpose, Unpivoting, Sorter and Joiner are the nodes to solve this:
odd-even.knwf (33.4 KB)
To select odd and even column headers (which are actually the rows in the original table) in the Unpivoting nodes I have used these regex patterns:
For even columns: Row\d*[02468]
For odd columns: Row\d*[13579]
