Sure. Here's one. LW's own quantum physics sequence discusses systems undergoing continuously branching evolution. Even non-MWI books are fairly explicit pointing out that the wavefunction is continuous but we'll study discrete examples to get a feel for things (IIRC).

In fact, I don't think I've ever seen an MWI claim outside of scifi that postulates discrete worlds. I concede that some of the wording in layman explanations might be confusing, but even simplifications like "all worlds exist" or "all quantum possibilities are taken" implies continuous branching.

It seems to me like continuous branching is the default, not the exception. Do you have any non-fiction examples of MWI being presented as a theory with discretely branching worlds?