Yes, teachers can see all the Writable scores auto-populate in Google Classroom, adjust them as needed, then click 'Return' to send scores to students when they are ready to make them "official".
To return a score in Google Classroom:
1. Click into the Writable assignment in Google Classroom, choose the students, and click 'Return'.
2. Enter a comment for the student (optional) and click 'Return'.
3. The student will now be able to see their score on the assignment page or on their list of assignments in Classwork: