For split over/under shots, a single full-frame underwater filter can make the above-water part look wrong, because the two halves of the image have very different color and brightness needs. In practice, people often use split or graduated filters designed to affect only part of the frame, and/or add underwater strobes to brighten the submerged portion.

A bigger challenge than color is exposure contrast: the scene above water is usually much brighter than the scene below. That’s why split-shot photographers often rely on graduated density/split filters and underwater lighting rather than a simple all-over color filter.

If your camera supports RAW, that can help a lot with white-balance correction afterward, reducing green/blue cast without baking in a filter effect across the whole image. But even then, underwater light loss can be significant, so split shots remain technically difficult.

So yes: a normal underwater filter can hurt the topside half. For this kind of image, split/graduated solutions, careful exposure, and sometimes strobes are the usual approach.