How can I remove q2a link and add my site link in atribution. For example--- powered by Ask Answer
You can add below function in qa-theme.php file of your theme.
change this function as per your requirement.
Welcome to the Q&A site for Question2Answer.
If you have a question about Q2A, please ask here, 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.