The female model for the scuba suit has big male pecs and I find it kind of amusing. Also, no flippers (still not sure if that affects my swimming speed though) :
Scuba Suit | GTA Wiki | Fandom
GTA 5 Cool Outfit - Tactical Scuba Suit - YouTube
Diving Motion - GTA5-Mods.com
Most Expensive Clothing in GTA V Online - Pro Game Guides