Yes there are many Hare Krishnas in China, but they are not public about it. It’s forbidden to chant on the streets and even kirtan in houses has to be very quiet. The government is less restrictive than it was and the numbers are growing steadily, but I don’t see a dedicated temple being built anytime soon. A good number of Buddhist temples were destroyed by the Communists so they aren’t likely to sanction any new ones soon. To fill the gap that atheistic communism creates the government is encouraging interest in Confucianism as it contains valuable teachings without acknowledging a Supreme Person.