I cannot find one.
I can make one, but I'm not a trailer expert. I've read of some hitches that attach to the rear axle, some that attach to the swingarm, and some that attach to the subframe. What I can't find is technical guidance that indicates why one is preferable to the other. And I can't find any to purchase, nor can I find a picture of one to copy.
I'm sure such a thing exists. Many sportbikes have used trailers, and the XX has a fairly standardized frame and chassis.