The Google app has a screenshot editing feature in beta

The Google app is now rolling out a built-in screenshot editor with beta version 7.21, starting last Friday, which will give users better sharing and editing tools, as spotted by 9to5Google. The screenshot editor also works in Chrome custom tabs. You can enroll in the beta through the Google Play Store.
The editor can be toggled on by heading into the Google app settings, under Accounts & Privacy and finding the “Edit and share screenshots” toggle at the bottom of the list. Then