Co-authoring tool with LaTex support

I am looking for suggestions for a collaborative writing and editing tool that supports LaTeX and imports nicely into Pressbooks. We have a textbook written by 2 authors that is undergoing substantial changes and the authors want to work together on the text but GooglDocs is not an option for them because of the LaTeX. They want to use Overleaf but I’m not sure how that will import into Pressbooks. Open to any and all suggestions.

This is probably too late to be helpful, but the first thing I thought was you could have them edit directly in Pressbooks. I am curious what you used as a solution.