Thanks for sharing your personal DAM flow and thoughts on it!
Exports end up in subfolders to the above most often web and export.
Do you use Digikam’s built-in non-destructive editing and Batch Queue Manager for this purpose? Consider you have a fresh photo imported into img/2023/0823_foobar under filename 202308231300_FJ_123.dng. Then you made several editing rounds therefore have more related files in the same directory:
202308231300_FJ_123_v1.png202308231300_FJ_123_v2.png
What filenames will be listed in img/2023/0823_foobar/export directory?