What calf reduction method is most effective? (Photo)

Your deformity and asymmetry are within normal limits. Regarding particular surgical procedure to reduce size of gastrocnemius muscle (two bellies) the most accurate technique is partial resection of the muscle belly. Considering pattern of innervation of this muscle, partial denervation is not possible without meticulous dissection of the nerve within muscle, what would require extensive scar.Discuss your options and expected results with your surgeon in details before undergoing surgery. Good luck. 

I see the mild asymmetry you mention but think your legs look perfectly fine.Procedures to reduce calves are infrequent and results can be unpredictable unless they are mostly fatty and lipo can help( not likely from your history and photos).There is an expression in surgery: "The enemy of good is better"i.e. when you have something that looks very good and try to make it perfect that is when things  goes wrong