[janipani]

Snow-fruit could differ from ice-fruit in various ways. We have seen fire-fruit and lava-fruit too. Devil fruits seem not have any rule that prevents similar abilities existing, only thing matter is that theme changes, and these themes can be from nature as well as from technology.

Snow fruit could be about snow storms, snow walls and all type of snow as long it's under snow theme.

Ice theme is different, it can freeze things even though hardened snow could be seen as the same.