Yes, neuropsychologists can diagnose ASD, in fact they are probably the most qualified/have the best assessments for diagnosing it. My diagnosis was made by a neuropsychologist.
However, they do not diagnose based upon an uneven cognitive profile. An uneven cognitive profile would probably suggest an issue, maybe but not neccessarily ASD depending on how it is uneven. An ASD diagnosis will be made based upon the two main criteria in the DSM: impairment in social interaction and restrictive, repetitive behaviors and interests. Other common issues related to autism such as sensory sensitivity can also contribute to the diagnosis, but those two main criteria must be met.
