Is there a way to fix scar tissue in the lip, or make the other side larger to match? (photos)

 Hi, I have performed many lip augmentation procedures using dermal fillers or lip implants for over 30 years. Following my beauty principles, the lips should be full with the upper lip approximately 75 % the size of the lower lip for the lips to appear balanced. An experienced Lip Augmentation Surgeon can shape and augment one or both lips using a dermal filler.
 Dermal fillers and lip implants offer a much more reliable volume for augmentation of the lips than permanent fillers or fat injections which are associated with increased, unwanted, side effects.
Hope this helps.

Thank you for your question and photos
Some scar tissue may be minimised with steroid injections depending of the tissue injury, however it is very difficult to create an even and smooth result particularly in the upper lip area that you are concerned about.
I would suggest augmenting your lips with an appropriate type and dose of dermal filler to achieve a more symmetrical and even result to your upper lip.
I recommend you consult with an experienced and highly trained practitioner.
Best wishes