These people are against foreigners, for a strong police and military (in fact, some vigilantes in China seem to be directly backed up by government authorities), are racist, anti-religious, for Chinese imperialism (e.g. in the South Chinese Sea), and so on.
If you e.g. make a Youtube video criticism state policies in China, these people will try to find out who you are, your address, your family, etc., and then bundle up online to discredit you at your employer and at state authorities. Tons of death threats will enter your email inbox and they will accuse you of being a traitor to the fatherland. That's obviously right wing and fascist (coming from "fasces", the rods used to beat up people on the streets of ancient Rome).
The atrocities of communism are justified very differently, based on a fairly complex ideology. "left wing" would e.g. be if these people founded workers committees in which they'd force colleagues to discuss their "reactionary imperialist ideology" and confess their egoistic betrayals of society. It's different from "right wing" in dozens of respects, especially the justifications.
Of course, extreme right and extreme left coincide about totalitarian stances, and sometimes also use nationalism and populism to further their agenda. But they disagree about all the rest.