Is there any way for Google Photos to Sync with Computer, not just Backup for any Editing?

You can easily backup photos and videos to Google Photos account. But, it does not allow you to sync your photos and videos with your desktop. What if you edit, delete or add photos on phone, as well as on your computer in a Photos folder? If you edit your photos with an external application on your phone, then go to "Photos" and tap "Menu" icon and then select Local Folders and make sure that edited photos are set to sync to Photos account. If you edit photos on your computer, then first create a folder on your computer and add those edited photos into it. Now, set the Google Photos Backup desktop application on Mac and include that folder in "Backups" to Google Photos on the cloud.

If you use iPhoto to edit your photo and want to backup those edited photos to Google Photos, then you can easily move them to Google Photos using "Google Photos Backup" application on Mac.

If you do not know how to move iPhoto Library to Google Photos on Mac, then you can follow the link provided here.

You have another option to sync your photos from computer to Google Photos i.e. using Google Drive Desktop application. You can keep your Google Photos folder in Google Drive folder. So any device's photos syncing to your cloud will also sync to Google Drive. But, when you sync photos via Google Drive, it always count toward your storage limit.