I agree with above comments, his only weakness is his 6'2" height, ideally I wish he was a few inches taller, with a longer reach he might have just have kept out that superb free kick on Saturday, or stand a better chance saving penalties?
Having said that I still wouldn't swap him for anyone in the PL, just being a little nit picking ;-)
Height an penalty saving is not related IMO.
This is by no means a scientific study, but one of the best keepers vs. penalties recently has been Diego Alves the former Valencia keeper. He is the same height as Ederson and has saved 46% of penalties he's faced, at one point it was about 50%. The best penalty saver in premier league history is Dmitri Karine, who saved 45% (5/11) playing for Chelsea - also Ederson's height.
Maybe it's like penalty takers, some are just good at them, some aren't. Maybe it's coaching though, or maybe he's predictable and other clubs have figured him out.