Personally if there wasn’t a shower I would have a bottle of water with me to pour over my boobs before feeding to avoid baby ingesting the sea water / pool chemicals
I went abroad and just fed her after being in the pool, occasionally wiped with a baby wipe. Once they’ve had their jabs they can go swimming so would put their hand in their mouth from there! They’ll be fine either way x
You don’t need to wash your boob. Sea water is salt water and pool water chlorinated! Maybe rinse your boob with some bottled water if you are worried and can’t get a quick run under a shower, but it’ll be fine without, I’ve breastfed my babies literally in a swimming pool and it’s never caused any issues! 😊