Correct me if I'm wrong, but there is no way to add a MathQuill formula to a matching question in the new quizzes, is there?
I cannot correct you because you are correct. There is a feature request for this idea: New Quizzes: Rich Content Editor (RCE) for Matching Question Types
I did some additional checking.
There is a lesson the Canvas Instructor guide that provides guidance How do I create a Matching question in New Quizzes?
The first paragraph in the notes section says: "In a Matching question, students are required to match answers from a drop-down menu with a list of questions."
Since you're getting a drop down question, you're not going to be able to put fancy content in there. Both the left side and right side appear to be text-only.
I did go into New Quizzes in our beta instance (we don't have it enabled in production) and create a matching question. The formula button is not available for the answer section and I was unable to get the LaTeX code to show up when entered manually.
Unicode is supported, so you may be able to fake it if what you need to enter is relatively simple.
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