Interesting and thought-provoking piece, though I wonder if it sets up a slightly artificial distinction between "chosen" and "preferred".
Surely you would *prefer* to be called by your *chosen* pronoun rather than by one you consider incorrect, and therefore it is both chosen *and* preferred?
But at the same time, I understand that "chosen" is quite a bit more definite, whereas "preferred" might imply it doesn't really matter very much...but maybe you slightly prefer this one...
The solution mentioned below by Byrcha V, simply saying "my pronouns are...", seems to solve the problem neatly.
Whether other language users agree is obviously a different matter, but at least it makes your position completely clear, and it doesn't imply that you have fancifully chosen a pronoun from a large set of possibilities - it asserts the correctness of a certain pronoun as fact.