Hi, good question, you can do this by tags or also by making one product system per life cycle stage and then add these different life cycle stage product systems to one overall life cycle. We have shown this principle for EPDs in the EPD live webinar (check on youtube, openLCA channel). In the impact analysis, you can unfold results up to the LC stage, and then copy and paste to excel.
It is a good idea to have this chart in openLCA, since the information is there (this is for us, as developers). So thank you for the question and suggestion!