I'm glad your going to put the time and training into your pups.
All my dogs have been adult rescues. Most dogs from a reputable rescues don't have issues basic training can't fix, it's just that sadly they have sometimes had no training prior to coming into rescue. Most will be worked with while in rescue to give them basic training and manners. Many older dogs will actually have some training and already be house trained and are in rescue due to no fault of their own.
None of mine have come from a reputable rescue though, I've got mine as give aways or from the pound and my current dog I picked up as a stray and his 'owners' didn't want him back. Good for him though as he'd been abused and I really didn't want to have to give him back. Now he's a lovely friendly dog who thinks everyone loves him instead of the timid dog who'd run and hide if you tried to sweep the floor or water the garden.
I also took in a dog many years ago that I did not know at the time had extreme dog aggression issues, he also had no training at all. I trained him all the way up to competitive obedience level and was able to free run him with other dogs to play so old dogs can learn new tricks.
I'm sure you'll have your hands full with two pups in the house and look forward to seeing pics.
I've only ever met one Portuguese water dog, he was a nice boy but he had very little training. He was very protective of his house and the kids in his family.