In my opinion, I won't say the MC is a psychopath, sociopath or whatever because that, as far as I know, are more modern designations to mental diseases, from what I read and saw, while considering the entire setting:
1st: The Mc is an Onmioji, and according to Wikipedia: Onmyōji were specialists in magic and divination. Their court responsibilities ranged from tasks such as keeping track of the calendar, to mystical duties such as divination and protection of the capital from evil spirits. They could divine auspicious or harmful influences in the earth and were instrumental in the moving of capitals. It is said that an onmyōji could also summon and control shikigami.
2nd: The MC world has all those spirits in flesh and bones, so we can consider him as some sort of spirit hunter, he was a master of a 'spirit hunter' dojo, but then according to what he said in the first chapter the Imperial court branded him as a traitor while his disciples were being held, hostages. So he had enough influence to be considered a threat to, what apparently is feudal Japan, so we can consider him as also being a Samurai or so, so he had at least some noble standing in his past life
As an example of what happened in this comment section, it would be like saying that George Washington was a psychopath for crossing the Delaware River in winter with the British Armada patrolling the river because that plan put the lives of hundreds of American soldiers at enormous risk
3rd: He's calculative and very self-restrained something completely opposite to a sociopath, but he at same time has a lot of restrains and empathy to be a psychopath. Because for the three categories of psychopathy he doesn't fit in any of those:
One includes lacking fear, high confidence and social assertiveness. He doesn't show fear because he has experience on his side, and he isn't overconfident, nor he imposes his social standing
another type includes poor impulse control and lack of restrains, two things that he shows the complete opposite
the last one includes lack of empathy, lack, and disdain of close attachments, use of cruelty for self-empowerment, exploitative tendencies, defiance of authority and destructive seek of excitement, again he shows empathy (to Efi and his older brother), has close attachments to Efi (so much that when his plan ends up almost injuring her, he rushes in to save her), he only used his powers to scare his brother once, he didn't defy his father, and he doesn't seek excitement by doing evil deeds, the only part he truly fits in the use of the exploit of his family tradition
So from what I read and quickly researched, he's way too far for being a psychopath, at best he lacks deeper emotions because of his past life and what it required of him, something we don't know about