I’m not putting this in bug reports because I don’t have evidence but in the last 20+ underwater structures I’ve checked, not one of the sharks was not a regular shark. This along with the low amount of natural shark spawns, makes large sharks practically impossible to find.
I’ve been hunting for multiple days now and I’ve seen two megolodons and no other large sharks, of course neither of those megolodons dropped the egg I needed, so I kept hunting and kept finding none.
tbh its honestly easier to just be sailing around until a white eyes or something spawns, then go to the closest island and kill it from the land. thats how i got mine, just beach a white eyes and spam attacks