Do you or don't you

This sounds better to me.
You may not let me to choose, will you?

Hi,
Your statement is not correct, and I would not even bother to put a tag on it.
In fact, I would also substitute may for might, so that the sentence would read better.
As it stands, your statement seems rather awkward to me, so to prevent this awkwardness I would write:
‘You might not let me choose.’ Strictly speaking, the tag question of this statement should be ‘

I wonder whether native speakers might say

You may/might not let me choose, won't you?

To me, the use of "won't you" sounds as if you want to express your concern about not being able to choose ( and possibly reverse the decision in your favor. This is probably similar to asking "Won't you let me choose?")

I am with Regards, This is one of those cases that if you follow the "tag" rules, you will have to use "might you", which not only is quiet uncommon, but also sounds stiff.

IvanhrYou might not let me choose, won't you?

By rules, we can't not mismatch modals, or use the same polarity

Actually , there are a lot of exceptions to what you're saying. One example I can think of is
Do listen, will you?

That said, I'm not sure whether the example I gave in my previous post is correct or natural and that's why I'm asking. The one you gave (You probably won't let me choose, will you?) is certainly correct.