wpDiscuz uses WordPress native comments functions and doesn't change the logic of the external website link system.
As this is WordPress native logic we'd recommend using some other WordPress plugins e.g theComment Link Remove plugin.
After installing this plugin you'll need to enable the "Open Comment Links in New Tab" option. This option is located in the Dashboard > Settings > QC CLR Settings admin page.
In case you want to say thank you! 🙂 We'd really appreciate if you leave a good review on the plugin page. This is the best way to say thank you to this project and the support team.