Merging 2 photo libraries on 2 iCloud account ?

I am sorry to hear about your loss. My condolences.

To save your wife's photos: The method suggested by Alma1090 will work, but you will save just the photos, not the photo libraries with the albums, the adjustments, etc.

As you have a Mac and are using Photos on a Mac, I would merge the two libraries on your Mac. It will be easier, as Photos on a Mac is more powerful than the iPhone version.

Can you access your wife's user account the iMac?

• Open Photos in her user account.
• Make sure, that your wife's Photos Library on the iMac is in sync with her iCloud Photos Library, but all photos have been downloaded from iCloud. Disable "Optimise Storage" for her Photos Library (Photos > Preferences > iCloud) and wait for her photos to download from iCloud.
• Add a keyword "Her Photos" to all photos in Photos. Select all photos at once with ⌘A, open the Info with ⌘I and type a keyword "Her Photos" into the Info. Now you can find her Photos in a search or use the "Showing only" filter to see either your photos or her photos. You my want to tag your own photos with keyword "My Photos" in your user account as well.

Then I would copy her Photos Library from the Pictures folder to an external volume with plenty of space. Prepare this volume as described here: Move your Photos library to save space on your Mac - Apple Support

It is important to set the "Ignore Ownership on this volume" flag, or you may encounter permissions problems, when you try to open her library from your user account.

Now you can merge her Photos Library with your Library in a lossless way, simply by opening the copy of her user library from your user account.

• Sign into your user account. Launch Photos while holding down the options key ⌥ and select her Photos Library on the external volume.
• Make this library the system photos library (Photos > Preferences > General: Use as system photos Library).
• Make this library your iCloud Photos Library (Photos > Preferences > iCloud: iCloud Photos)

Now the photos from your Wife's library will be merged into your iCloud Photos, photos and albums, all metadata tags, like titles, keywords, places, named, faces, etc. This may take several days, if the library is large.

Once the library has been uploaded into your iCloud Photos Library, you can switch back to your own Photos Library on your system volume, if you have enough storage there.

I would make a backup copy of your own Photos Library and your wife's library, before you start merging the libraries.

Hello and welcome to Apple Support Communities, alexgodlexxx!

We understand you want to add your wife's photos to your Photo Library. We'd be happy to provide information to help you accomplish this.

First of all, sorry for your loss. We want to make this as seamless as possible. Since you no longer need her iCloud account, you can download all of the photos directly to her iPhone by going to Settings > [your name] > iCloud > Photos, and setting it to download and keep originals. You can monitor the download progress by opening the Photos app, scrolling to the bottom and seeing the amount of photos still downloading. Once it's done downloading, go back to Settings > [your name] > iCloud > Photos and turn off iCloud Photos.

Now, to get the photos over to your Photos app for Mac, follow these steps: Transfer photos and videos from your iPhone, iPad, or iPod touch

As far as the keywords to identify which are hers and which are yours, you can go to the Recently Imported tab on the Photos app for Mac and add the tags there. Keep in mind, some of your photos may appear on Recently Imported, so selecting all is probably not a good idea. This article shows you how to add keywords: Find photos by keyword in Photos on Mac

Have a great day!

It would be better to create a second volume on your Time Machine volume.

Even if you disable Time Machine, the backups will remain on the volume and prevent you from using the volume for Photos. And you really do no not want to delete your backups.You may need them one day.

The copied Photos Library should be on a drive with a wired connection, not on a network share, or you will open a can of worms.

Hi - also from my side - deepest condolences.

The problem with Optimise storage, is when you turn it off, photos doesn't automatically download everything - it tends to download originals as needed (ie when you need to use them)

The simplest solution is probably to create a new empty library*, set it to be the system library without optimise storage, and then let it sync to the first iCloud account. When complete, sign into the second iCloud account, and let it sync there.

That should force a download of all images. Obviously for this to work, you need all the images to be in iCloud.

*Option key launch of photos, Click create new. Name it (eg) "merged library". Open it. photos>preferences, click "use as system photo library". Make sure iCloud photos is enabled. Leave mac on connected to power with photos open until the dowload is complete. This might take some time for a large library (Days or even weeks).

Get back if any of this is not clear, I've kept it brief because it sounds like you already know what you are doing.