iku55

Looking at the previous translation file, it seems that death.fell.accident.water has been deleted from 1.16.

Can confirm in 21w37a.

This is the same type of problem as MC-187732.

The same result was obtained for cactus.

Obsidian is placed north and east of water.
Lava is placed south and west of the water.

I expected what was going on.
I think the fill command places blocks and updates surrounding blocks in order from the north and east corners.