The best option would be to have a “regular” client that keeps a local copy in sync with the cloud instead of a mount.
BTW: IDK what cloud storage you are using, but IIRC some show files that are not available locally (ie. only the most recent files are downloaded locally - the older stuff is downloaded on request).
Alternatively, you could hack something together running unison locally in the guest to sync the cloud folder to a shared one… you’ll have two copies of the data though.
“mesh” is a buzzword that doesn’t make much sense (to me at least) if we are talking about wired and routers… what do you mean by it? can you describe your setup?