Possibly there is a distinction between a 代名詞 (pronoun) vs. 助詞 (particle). The 3rd person pronoun usage of 之 and ordinary relational connector 之 might be sufficiently different to be considered separate.
There might be a separate entry for 之 (動) for 動詞: the verb 'to go', also a meaning of 之.
I do not think a meaningful answer can be had for the following reasons:
First of all, one needs to define the word "know". What exactly do you mean by "knowing a Chinese character"? If I can recognize and sound out the character when I read, but I have never used it myself, do I know it? I suppose this would be a very passive kind of ...