WinSCP indeed does not support moving/renaming S3 folders.
In the s3 right pane, I select a folder(s) to move. I type the folder in the popup the destination in the same bucket, just a different root folder. Winscp returns error, cannot move folders.
When I use an alternative android s3 app to move the same folders. It's finished in minutes.
Folders in the bucket have 1000s of files or no files just empty purged folders. Same hang result in winscp.
Winscp version: latest
Connected to s3 compatible bucket (wasabi storage)