I’m sorry, but I don’t believe this is presently possible in Brave. That said, we are working to add support for extensions in an future release, which will allow ua-switching. If you don’t mind, what is your use-case for this request? Thanks!
Hello, @boilscighxu. You can achieve these results by blocking Scripts on the page. To block scripts, click the small lion () icon to the right of the address bar, and turn off scripting. I hope this helps.