Is it possible to slim my wide Asian nose with a rhinoplasty but without an osteotomy? (photos)

The best way to determine what specific changes will look good on your face, and what changes are surgically possible, is to do your research to find the top rhinoplasty specialists and consult with several of them in person. During your consultation, your photos can be computer-morphed to show how the changes to your nose will affect your appearance. A rhinoplasty specialist will have the experience to determine whether the morphed images are surgically attainable. Good luck @drdonyoo

Yes, in many instances, if the cartilaginous part of the nose is wide (usually the lower 1/2-2/3), it is possible to bring these tissues inward using excisional &/or suture techniques. Also, if the bridge is augmented slightly using material (fillers or cartilage) that is narrower than what it rests on, the nose will appear thinner.

Hi and welcome to our forum!
From your photos, I note a broad nasal base, a broad drooping nasal tip, and a slightly high dorsal line.
Correction of the nasal tip can be performed without osteotomy. However, one cannot narrow the nasal base if the nasal bones are still attached to the maxilla (as they must be mobilized). One cannot lower the dorsal line without osteotomy of the nasal bones. With these restrictions, I don't feel that a partial rhinoplasty would provide a satisfactory result. Narrowing the nostrils to a point where breathing is obstructed is extremely unusual.
Visit a board certified plastic surgeon for evaluation and discussion.
Best wishes...