Searching this Forum for multiple-file export solutions, i've read this is possible only to Cloud via Files App? Not good for me: any Cloud connection impossibly slow here.
I use the (free) FileBrowser App as my primary iOS file manager and find it solves this difficulty for me. (As with so many other tasks).
From Files App (ArtStudioPro folder) I can drag and drop - using SplitScreen - into any location in FileBrowser. The beauty of FileBrowser is that it can connect not just to other ‘on iPad’ folders, or to Cloud services, but directly, immediately, to any drive/folder on any Computer on the same wireless network.
This works both ways, and with other Apps as well - basically, making to-and-fro transfer of files, brushes etc, single or multiple, a really flexible and reliable procedure.
I thought maybe others might be interested…