How do export sidecar .xmp's for an entire hierarchy of folders containing photos?

[Remco Viëtor]

On lundi 23 octobre 2017 19:38:42 CEST daveg at justemail.net wrote:
> Hi,
> 
> I'm moving a collection of Photos to Digikam 5.7.0.
> 
> The photos are currently in a nested hierarchy of OS folders.  I've selected
> the top-level folder as my Album root.
> 
> In Digikam, I see & can navigate the tree, and can view images in any
> specific folder.
> 
> I want to export metadata to sidecar .xmp files for all the photos.
> 
> I *can* export for any selected group of photos -- but I have to be IN each
> folder with photos to do that.
> 
> How can I export/write sidecar .xmp's for the entire tree/hieraechy at once?

Could "Tools"->"Maintenance"->"Sync Metadata and Database" be of any use here? 
(Combined with the proper metadata setup in settings, of course).

Remco