I think that standard Q2A does not have its feature. However, if you enable Event Logger plugin, you can know it. By the way, NP is supporting only flag for moderator now. I will cover down vote in V1.5.
Welcome to the Q&A site for Question2Answer.
If you have a question about Q2A, please ask in English.
To report a bug, please create a new issue on Github or ask a question here with the bug tag.
If you just want to try Q2A, please use the demo site.