Use other apps and editing tools in Photos on Mac
You can download and install app extensions (also called plug-ins) to provide new editing tools in Photos. For example, third-party apps may provide specialized filters or other photo adjustments.
Download and use third-party apps while editing photos
Go to the Photos app
on your Mac.Double-click a photo or video, then click Edit in the toolbar.
Click
in the editing toolbar.Choose the app you want to use, or choose App Store and search for apps to add to Photos.
Follow the onscreen instructions to download and open an app.
The app now appears when you click
in the editing toolbar in Photos. If the app doesn’t appear, see Turn app extensions on or off.
You can use a combination of apps and built-in Photos editing tools to change a photo. When you click the Extensions button in the editing toolbar and choose an app, the extension or app opens with your photo active. Make your changes, save the photo, and close the third-party app window. The Photos window shows your changes; click Save Changes.
Turn app extensions on or off
Go to the Photos app
on your Mac.Double-click a photo or video, then click Edit in the toolbar.
Click
in the editing toolbar, choose Manage, then click 
to the right of Photo Editing.Turn each app extension on or off.
In the Photos app, click Done, then click Edit to return to the editing view.
Apps that are turned on appear when you click
in the editing toolbar in Photos. Apps you turn off are hidden.