Waterclips are clips that represent a water line of sorts on seaplanes. it's a 3d mesh thing. They must be referenced by number in the FM.
They are there, it's a question of their placement. The plane usually can be seen sitting a bit tail heavy in pictures, so it's not that wrong.

That first screenshot is from an early wip and not what the plane looks today. The orange plane shows a better up to date position.
A few thing that I also did was make the gun barrels only visible when a gun loadout is selected and eliminating torque, since that's what the counter rotating props do.



Being plagued with many particular design features that never worked right, the plane was first flown in 1941 but only became operational in June 44, with only 15 examples built. It was the first Japanese plane to use a counter rotating propeller installation, driven by a Kasei 14 engine. Eventually this was the only feature that worked properly. It also featured a laminar wing profile,
The verdict from the field unit was abysmal.
- center float emergency jettison never worked at all. it was a flawed design.
- Stabilizing float retraction was shaky at best, with floats often refused to redeploy, causing accidents. In the field, they were operated fixed extended. This reduced top speed, which would have been about 470 km/h @5000m with center float attached and stabilizing floats retracted.
3 were lost to enemy action for all I know.