Angelina yes and no, it depends on what kind of swimsuit you wear, besides most people would not think of a chastity belt if they did.
Yes,they may notice it,but would not think of a chastity belt.
No,I would fear too much someone notice it(even if not likely they understand what it is easily).
I think too hip-style ones are better to wear,especially as these are easier to hide,and so,allow us to wear more different clothes than with waist-style ones.
Not asked,but My-Steel,total chastity belt,with the cable rear;waist-style.