Stones is a bit like Rodri, Dias and Laporte are a bit more like Fernandinho.I know what you mean about the "look" test here and I was surprised at how good Dias appears through the prism of raw numbers. One thing for sure though he is clearly v v good. And reliable. One thing though is the percentages don't take into account the difficulty of the pass. Intuitively Stones is better.
Stones will mostly play it around to help set tempo and help kickstart attacks positionally. He isn't particularly bold but when he is he'll often do something very impressive with the ball (such as a low pass through the midfield breaking the lines and taking a bunch of opposition players out of the game).
Dias and Laporte also do that to a lesser extent but they're more aggressive about things. They'll bring the ball forwards more, they'll try the cross field pass a bit more, they'll try and play a pass through to the CF a bit more.
Neither is better than the other, but I do like the balance Stones and Dias give on this front when together. Stones and Laporte give us the same balance too although I'm not the biggest fan of them as a pairing defensively compared to other pairings.