I would say that in the case of China, religious freedom has been enshrined in the constitution since 1982. There are protections for minorities based on their religious affiliation and ethnicity. I think Canada does have to tread a fine line in statements, because it could be portrayed as meddling with internal Chinese affairs, but I think highlighting Chinese law and the Chinese constitution in the protection of these rights would be one way to go.
On June 18th, 2019. See this statement in context.