Search for "microscope camera adapter" on your favorite shopping sites. The same adapter should fit either eye-piece or camera port. The cheaper adapters have no optics. Without optics, images will have heavy vignetting.
Many of the microscope-camera adapters have T2 screw mounts on the camera side, including the AmScope model. The same adapter should fit either eye-piece or camera port. Use a T2-NEX adapter, instead of T2-Nikon or T2-EF, to fit it to your camera.
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