Well, there is the official CR Recap series of blog posts for the current campaign, which ... conveniently picks up right where my last canon catchup for Beau left off and gets updated after every episode covers episodes 1-106 so far, lol, I somehow didn't see the Next button on the page. (Also conveniently, knowledge of the Vox Machina campaign, while a bonus, isn't necessary to understand the Mighty Nein campaign.) The CR wiki also has some recaps as well as recaps for Campaign 1, though they're kind of scattershot and incomplete as fan wiki entries are wont to be.

There's a few YouTube channels with highlight clips and such, too. CR Memories is a good one with curated playlists, and Nico Neilson does some fun clips edited to focus on the players involved in a given scene and any particularly entertaining reactions from the others. (Do not recommend CR Highlights though as the person behind that account is a garbage person.)

Of course, visuals not being entirely necessary, running the audio in the background while doing other stuff works too and is how I caught up on a bunch of Campaign 1.

Listener discretion -- or more accurately "who's within earshot" discretion -- is advised, though, for language and whatnot.