Perhaps instead of looking for alternatives, you should try to get Dragonfly to work. It should work offline after an initial online connection which is required to download the latest version, or, if you are unable to do this, it can be downloaded directly from
https://github.com/operasoftware/dragonfly
For more details, see this dragonfly blog post, and remember to update the "Developer Tools URL" in opera:config
to point to the location of your downloaded client.xml
file instead of the default https://dragonfly.opera.com/app/
(which would require an active connection) as per this comment.