Fat transfer after breast reduction
You can definitely have fat transfer after a breast reduction. It's a great option to correct asymmetry. You shoudl wait at least 6 months before doing this though.
Fat transfer is an excellent option for breast asymmetry. I would usually wait 4-6 months after your original surgery. We have an office in Beverly Hills that my partner Dr. Kamran Khoobehi sees patients. We would be happy to see you. Please be sure to see a board certified plastic surgeon who has a lot of experience in breast fat grafting.
Asymmetry following breast liposuction
You absolutely can do fat grafting on the smaller side to improve symmetry and shape. I recommend waiting 6 months after your liposuction to go forward with revision.