But you should be aware of that Google Photos will separate meta info from photos. So later if you want to download them all you will get JSON files and photos.
Only way to get with meta data, is to download they by hand, you can select 500 at a time.
Here's another way:
plug in an external disk or storage.
Create a folder on it.
Open Photos and select all the videos.
Drag them to the new folder.
Wait a LONG time for the export to complete.
Sort the new folder by size.
OR, if you're happy with keeping them there, go back to Photos and delete them. That will save more space than is in the new folder, ...
I've had "1 item" like you for a long time now, but I figured out how to find it.
On your Mac, create a Smart album
Select "Filename" "Does not include" and then list several file formats, like:
Demo smart album:
The "1 item" I finally found:
I would move your Photos.app Library to a large external volume. Follow the steps in this Apple Support document:
(Broadly, quit Photos.app, then move your library in the Finder, then launch Photos and in the preferences point it to your new location. Designate the library as the 'system library'.)
Once you've done ...
I think you have two options here:
Download the images and save them to your external hard drive
Create a photo library on the external drive and use that one with iCloud enabled (however iCloud is not a backup service, only a syncing service, so you'd then also want to backup that drive)
For the first option there are multiple online guides:
iCloud to ...
No, the pictures will still be available on your iPhone if you click Turn off & Delete. The images will then be deleted from iCloud within 30 days.
No matter what, I would definitely make a backup of preferably both your iPhone and the Raw photos/videos e.g. to an external hard drive to ensure even if something goes wrong you don't lose your data.
Thanks so much for this answer. It worked great for me! But I do have one suggestion. Over time, Photos may stop syncing again, so I keep a simple image on my desktop so I can add it without having to hunt around for a new photo. But once Photos starts syncing again, I remove the image. No sense having multiple copies of the same image in Photos.
Select the photos you’re interested in.
Menu-select Export, submenu export originals
Put them anywhere you want.
Edit: Having been alerted that I haven’t answered the question at the end, I decided to not delete this as it may be useful to someone else.