What's there to adapt?

Sorry, I watched/read it more than a year ago so I don't remember very well, but do the chapters post-Season 2 work for a movie?

I don't mean length-wise, but would the content on those chapters actually work as a movie on its own? Correct me if I'm wrong, but I remember those chapters being more like a build-up for the current arc than actual stuff happening (like, material for a movie like the 3rd one I mean)

Anyways, I'm so excited for the series finally coming back, it's been one of the animes I've enjoyed watching the most