Onana is a really strange one. His technique (if that's what you can call it) is really unorthodox. He's made a few really good saves, but his general shot stopping is pretty dodgy.
I remember Peter Schmeichel saying he didn't look like a proper goalkeeper a few months ago.
It's like he rolls a dice in his head to pick where he's going to position himself, I'd love to see a diagram of the goals he's conceded versus a 'normal' keeper, he always seems out of position and even his saves feel more about him having to dive to cover his positioning being poor.