In case you need a stencil for making your own Genkouyoushi paper for studying Japanese, here it is. I chamfered the edges so it's a little easier to get down into the space itself.

The inner square area is 7 by 7 millimeters, because that's what Google said was the right size.

Make sure that it's 2mm tall to get the correct square sizes! Cura upscales it automatically.