Not sure there is such a shape.
In order to satisfy the Euler characteristics, the shape must have 8 faces and so is an octahedron. But there seems to be no octahedron with 9 vertices.
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nonagon
a shape that has 9 faces
There can be no such shape.
An octagonal pyramid.
The shape would be impossible. The faces and vertices have to add up to two more than the edges.