Removing '._sync_*.db' files

I am trying to transfer a large BagIt bag to a processing service.

When I sync the bag from my local machine to Nextcloud through the sync client, it appears to add a ._sync_*.db file to the bag. This breaks the processing service for the bag, since that file is not in the manifest. The Nextcloud sync client’s ‘Ignore hidden files’ option seems to be non-functional on both Linux and macOS clients (does not stay unchecked), and I can’t tell the client to ignore these file types either.

Does anyone have solutions for this, or have you encountered this problem before?