Dear minafogiovanni, such an output is not available from Engineering 2D. I see 2 solutions:
A. Output the values and coordinates for all the nodes (Troubleshooting, 2.2.21 How to get the nodal forces at 100 nodes as output in text-file or other?), then filter using the Reference Nodal Coordinates (see also ATENA 2D User's, 2.8.4 Result Data Structure) in a spreadsheet (or some other program).
B. Export the results (File - Export - Binary result files), then start ATENA Studio and create a project from these results. There, you can define a Selection and write output for this selection (see ATENA Studio User's, 4.3.2.1 Data Request and 3.7.4 Selection Manager).