Less of an axis and more of general left-center-right, all with regards to which news outlets tend to lean one way in tone and language choice vs. another. You can select summaries of each bias to understand those choices in the app. It also helps break down a few other items of note:

While this may be beyond the scope of your efforts, it does do some solid highlighting of news sources for me.

There are a few Ground.news bots floating around Lemmy -- or at least there used to be -- that would comment on posts to provide some or all of the above.