I think for me she would have to directly convert the water to steam (which was not the case with hydroman). In the way you mentioned it she did convert the water to vapor but she didn't directly do this. The radiation or direct sunlight was what caused the phase change.
I think she should definitely be able to directly cause a phase change with water as we have seen her do this by changing water to ice directly. I just can't think of any instances where she has directly converted water to steam.
I think aritsts are just super lazy when it comes to her missing pupils. unless she is constantly viewing the world in energy form which is not the case.