To me swimwear coverups/post swim fall into a few categories:
Beachy glam-the sarong or sleeveless dress variety, add metallic sandals This is assuming you've already dried off.
Throw on and go- when heading home from the pool and don't feel like changing cause its 95 degrees out. Swim skirt, mesh, or otherwise chlorine proof.
Water sports (SUP, SUP yoga, kayak or the like)- I use a skort and matching tank (finds), optional bikini underneath.
Post swim cozy (capsule in progress)- something comfy and loose to put on after doing laps when its cold and you don't want to put workwear back on.