Since it's artificially crafted character, it's not part of unicode, therefore the transmission of the character will be through images, so to ban this character it's no different from banning Winnie the Pooh pictures, by using state-of-the-art deep neural networks to classify images.
To avoid the ban, one has to use the most common characters which must be statistically insignificant to computer recognition programs, like how most network apps obfuscate their traffic to https.
If you're asking about an electronic ban, it's irrelevant since this is a recently invented character and is not represented in Unicode, etc.
There is currently no censorship in Hong Kong and no laws which would require them to censor anything.
Ban what exactly?
They banned cryptography in Australia recently so we can't safely assume weird characters are safe neither.