Your asymmetry is due to pre existing asymmetry not implant selection. Only a lift would improve asymmetry and probably not worth the scar in your case.
From the photographs provided it looks as though there was some asymmetry prior to the breast augmentation. In my opinion is relatively modest. Only another operation would correct this and probably would involve the mastopexy. You probably should accept the result.
In your preoperative photos, you have an asymmetry. The right side is slightly larger and the nipple slightly lower. Your preoperative right breast has less superior pole fullness as compared to your left. Your BA made these subtle differences more obvious, but gave you an improved superior pole on your right side. Saline implants would not have made a difference. Overall nice result. Good luck and be well.
Your breasts were naturally asymmetric prior to surgery. That is fully reflected in your post surgical results. You need to speak with your plastic surgeon and see how this could be resolved. This is a situation that can be tackled preoperatively, so you know what to expect. I would need to evaluate the patient firsthand, but it seems that you may be well served with a mastopexy.
You had the same issue before surger. If you want the right breast raised, then you need a small lift.
The good news is that most women's breasts are slightly uneven. If you are a bit uneven before surgery, this would need to be evaluated and determined, and therefore addressed during surgery possibly with different size or style implants. That being said, It does appear from your photos that your right breast appears to be smaller and if this is a problem for you four months after surgery, it is unlikely to get better on its own. Your best recommendation (if you feel comfortable doing so) is to discuss your concerns with your plastic surgeon. If you feel that a second opinion is your preference, make sure the plastic surgeon you select is board certified and experienced in breast augmentation as well as revision breast augmentation. Let's hope that you will not need any revision surgery, but the only way to determine what is the optimal treatment plan is to have you evaluated in person.
Best of luck to you.
When I look at your breasts prior to your surgery you had the same asymmetry post op that you did pre op. It's possible your cre ashes are different or that one breast is slightly more droopy. You may need a small lift on one side, so discuss the with your plastic surgeon.