Mental health professional here.
People (in the US) aren't diagnosed with "sociopathy" any more; the term has been replaced with Antisocial Personality Disorder. Below is the diagnostic criteria so that we all know what we are asking when we debate whether Evan is a "sociopath." Everything below is copied from the DSM-V.
Antisocial Personality Disorder
Diagnostic Criteria:
A. A pervasive pattern of disregard for and violation of the rights of others, occurring since age 15 years, as indicated by three (or more) of the following [under A. Criteria B, C, and D must ALL be met, too]:
1. Failure to conform to social norms with respect to lawful behaviors, as indicated by repeatedly performing acts that are grounds for arrest.
2. Deceitfulness, as indicated by repeated lying, use of aliases, or conning others for personal profit or pleasure.
3. Impulsivity or failure to plan ahead.
4. Irritability and aggressiveness, as indicated by repeated physical fights or assaults.
5. Reckless disregard for safety of self or others.
6. Consistent irresponsibility, as indicated by repeated failure to sustain consistent work behavior or honor financial obligations.
7. Lack of remorse, as indicated by being indifferent to or rationalizing having hurt, mistreated, or stolen from another.
B. The individual is at least age 18 years.
C. There is evidence of conduct disorder with onset before age 15 years.
NB: Conduct disorder involves a repetitive and persistent pattern of behavior in which the basic rights of others or major age-appropriate social norms or rules are violated [and has its own long set of diagnostic criteria the person has to meet]. The specific characteristics of conduct disorder fall into one of four categories: aggression to people and animals, destruction of property, deceitfulness or theft, or serious violation of rules.
D. The occurrence of antisocial behavior is not exclusively during the course of schizophrenia or bipolar disorder.
Diagnostic Features
The essential feature of antisocial personality disorder is a pervasive pattern of and disregard for, and violation of, the rights of others that begins in childhood or early adolescence and continues into adulthood....For this diagnosis to be given, the individual must be at least age 18 years...and must have had a history of some symptoms of conduct disorder before age 15 years....Individuals with antisocial personality disorder also tend to be consistently and extremely irresponsible....[which] may be indicated by significant periods of unemployment despite available job opportunities....There may also be a pattern of repeated absences from work that are not explained by illness....Individuals with antisocial personality disorder show little remorse for the consequences of their acts. They may be indifferent to, or provide a superficial rationalization for having hurt, mistreated, or stolen from someone (e.g. 'life's unfair'
...These individuals may blame the victims for being foolish, helpless, or deserving their fate...; they may minimize the harmful consequences of their actions; or they may simply indicate complete indifference. They generally fail to compensate or make amends for their behavior. They may believe that everyone is out to "help number one" and that one should stop at nothing to avoid being pushed around.
Associated Features Supporting Diagnosis
Individuals with antisocial personality disorder frequently lack empathy and tend to be callous, cynical, and contemptuous of the feelings, rights, and sufferings of others. They may have an inflated and arrogant self-appraisal (e.g., feel that ordinary work is beneath them or lack a realistic concern about their current problems or their future) and may be excessively opinionated, self-assured, or cocky. They may display a glib, superficial charm and can be quite voluble and verbally facile (e.g. using technical terms or jargon that might impress someone who is unfamiliar with the topic). Lack of empathy, inflated self-appraisal, and superficial charm are features that have been commonly included in traditional conceptions of psychopathy that may be particularly distinguishing of the disorder and more predictive of recidivism in prison or forensic settings, where criminal, delinquent, or aggressive acts are likely to be nonspecific. These individuals may...have a history of many sexual partners and may never have sustained a monogamous relationship....They may have [many associated disorders such as anxiety, depression, substance use, and disorders of impulse control]." . . .
My mini-diagnostic formulation of Evan based on the DSM-V criteria (for any interested):
Re:1 - Evan did raise money under false pretenses, but the orchard WAS built; he didn't keep the money for himself. Aside from forgery and other actions related to the Connor Project I'm not sure what illegal actions he performed. While his actions in the show do not constitute model behavior, they are not emblematic of a pervasive pattern of failing to conform to societal laws since age 15.
Re: 2 - Deceitfulness - yes, clearly Evan engages in deceitful behavior. It is debatable as to whether he does so "for personal profit or pleasure" or if he initially lies out of severe anxiety, making his rise in social standing, relationship with Zoe/the Murphys, etc., are secondary gains from that lie as opposed to the original object of the lie. The fact that he perpetuates the lie in order to maintain his relationships with Zoe and the Murphys DOES indicate lying for "profit." It is not airtight, but it fits.
Re: 3 - Impulsivity - yes, Evan is impulsive in some ways. In others, he is painfully avoidant (skipping dinner because of being afraid to talk to the pizza guy?). In any case impulsivity alone is hardly grounds for diagnosing a teenager with a personality disorder.
RE: 4-7 - Not supported: He is irritable at times, but he never assaults anyone. He is not "consistently irresponsible" in terms of failing to meet obligations (i.e. he is not truant, he shows up to do the assembly speech despite being anxious, etc.). And, most importantly, he distinctly shows remorse and understanding that he committed wrongdoing in "Words Fail."
B: Is Evan 18 yet? If 17, he does not meet criteria. Diagnosing an 18-year-old with a personality disorder is rare but can occur when all criteria are soundly met.
C: There is absolutely NO evidence of conduct disorder prior to age 15.
D. Evan is not schizophrenic, and it is unlikely that he has bipolar. (though there are many types of bipolar so it can't be eliminated). So this one passes.
Looking at the diagnostic features, it is clear that Evan does not fit the "mold."
I would not diagnose Evan Hansen with Antisocial Personality Disorder. Criterion A.2 and D are the only ones that definitely fit, and A.2 may be debatable.
Does Evan do some very wrong things in the show? Absolutely. Can his actions can be justified by his mental health challenges? Not remotely. But does he have Antisocial Personality Disorder, a.k.a. is he a sociopath? No.
If you made it to the end, congratulations on your fortitude, and many thanks.