The idle looks great but the swimming is a little robotic and awkward, I would make it more smooth, maybe less repetative if that makes sense? try a more eradic swim, Im not sure what name it is but the swim style that would really fit roblox would be the one that looks like a frog with the upper legs bending out and the lower legs inwards with the arms splayed out (sorry if its badly worded)
i tried making it to have diff movement
but it kinda looked wrong in a bit nsfw way so i changed it and was happy on how it turned out as a final product