the flower trick has worked for me, it requires a wet suit though and it can be very time consuming. you need to fill your entire inventory with flowers and drop any bells you may have.
go to the farthest end you can swim with the wetsuit where villagers can’t see you and wait there for 5 minutes. it doesn’t work all the time bc villagers still have a chance of pinging you for new catchphrases but at least they can’t buy or sell anything off you because your pockets are full of flowers.
It’s very time consuming and laborious but the diving trick works.
You fill your inventory with low worth, none trading items (shells, flowers, unidentified fossils etc) and swim out to the furthest corner of your ocean with a wet suit and wait five minutes. Swim back in and the first villager you see should ping you. Seeing as your pockets are full of worthless items your chances of them giving you a PWP are increased, but it doesn’t mean they’ll give you a PWP every time.
Certain villager types only give out certain PWPs so if there’s a certain PWP you want, find out which villager types gives that and then trap them on the beach so they’ll be the first villager you see after 5 mins and ping you.
It’s a pain in the back side and I gave up in the end and opted for more …. “frowned upon” ways to unlock them.