> tab 1 contains news outlet A's coverage of a story, tab 2 has outlet B's coverage, tab 3 has Wikipedia; summarize and provide references.
I think this is basically what https://ground.news/ does.
(I'm not affiliated with them; just saw them in the sponsorship section of a Kurzgesagt video the other day and figured they're doing the thing you described +/- UI differences.)
I am a ground news subscriber (joined with a Kurzgesagt ref link) and it does work that way (minus the wikipedia summary). It's pretty good and I particularly like their "blindspot" section showing news that is generally missing from a specific partisan new bubble.