How to correct lateral displacement without hindering flexibility? (Photo)

Your lateral pockets can be tightened to decrease side movement. Even with larger implants, you will still have a gap since this is your anatomy. I would not go larger, however, because you have thin tissue. Larger will look more like balls and tend to sag and push more to the sides.

Dear Funny566755,
breast revision surgery is the most difficult plastic surgery procedure performed. Botched breast surgery alters normal tissue planes and laxity, the ability of breasts to heal properly, and leaves scar tissue that dramatically affects the level of difficulty of the corrective surgery.Many patients come in to correct poor outcomes from their initial surgeries. The most common problems are due to implant malposition, bottoming out of the implant, poor scarring, and incorrect implant size.While the type of revision required will depend on the result of the previous surgery and the desired result of the patient, some revisions involve extensive pocket repair that may or may not need specialized external bras.If you are considering breast surgery revision, you should speak with a board certified plastic surgeon and have yourself properly assessed. Only after a thorough examination you will get more information and recommendations. Also, you have to make sure that your surgeon understands your breast augmentation goals.
Daniel Barrett, MDCertified, American Board of Plastic SurgeryMember, American Society of Plastic SurgeryMember, American Society of Aesthetic Plastic Surgery

This is a good question. The best option for lateral displaced implants is to have a procedure called a lateral capsulorrhaphy with internal stitches (with some medial capsulotomy dissection), where the surgeon will tighten the breast pocket laterally to prevent the implant from going off to the side, and open the pocket superiorly and in the middle to a small extent if needed. Sometimes mesh can help with this, but often times it is not necessary.
Using a wider implant will not help this problem, and in fact may make the implant look like it is going off to the side more. A more cohesive implant will not necessarily address this problem either, rather, it will help with preventing rippling (wrinkling) of the implant is above the muscle (as is in your case).
Internal stitches (capsulorrhaphy) or mesh should not affect your flexibility, however your range of motion and activity should be limited after surgery to prevent another malposition. It is very important to discuss your post operative regimen and activity status after surgery to ensure optimal results.