Pandoc can output to word. Writing in markdown and sharing the word output with editors/reviewers is a reasonably nice workflow — just treat the docx file as a pdf (or any other output format).
Yeah, I don’t have a great solution for tracking changes across multiple back-and-forths within Word, I use git with markdown for that. Pandoc is pretty ok with word templates, but the final version of a document will usually need a little manual tuning before it looks right.
A former teacher of mine was working on a way to do this with pandoc and Rmarkdown. The result is called redoc: https://github.com/noamross/redoc
It's still in beta though.
