At the moment, it isn't possible to move a maze from one project to another.
If this is something you'd be interested in, please share your feedback with our team!
Workaround
If you're on the Organization plan, you can leverage custom templates to recreate your maze in a different project.
To do so, add a new custom template from the maze, then create a new maze using that template in the desired project.
Learn more about custom templates
Please note that, because this is not a transfer, the original results, linked prototype, and paths won't be carried over to the new maze. However, this workaround can be helpful when you want to use a maze that already exists in a different project, but don’t want to rebuild it from scratch again.