Regarding AF for sports photography. I think we need to differentiate here.
There are many different kind of sports and as far as I can judge it with my experience with different brands, the newest Lumix cameras are good enough for 98% of all sports.
But there are special sports like soccer, field hockey, ice hockey and probably also baseball, football and basketball (team sports with crowds of people close to each other), which require special capabilities if and only if you do want to have no work at all, but still expect rasersharp faces of the focus players in the best position.
There have been photographers with manual focus cameras who were able to get the shot. But this requires experience with this sport and planning/thinking ahead.
Technically, such an experienced photographer will be able to make award-winning photos with a Lumix 5ii. The AF is fast enough und good enough for this. With 20 or 40 fps, you will have at least one perfect shot.
Obviously people with no or less experience in photographing that sport (like me) will have a harder time, no matter how fast our AF is or how many fps I have.
AFAIK there is no brand which offers a "dummy AF" which will make each shot perfectly in focus with these team sports. Every tracking gets sooner or later confused, if another body blocks temporarly the main subject. Or face recognition does not work because of helmets, rain etc. In sport this is very different than these youtube reviewers who hold something in front of thr camera for 2 seconds etc.
I did a lot of research over the last couple of days to find tips and trick from professional sport photographers of team sports. No matter which brand they used, none is 100% reliable.
If you earn your money with it and you have to deliver at least 10-20 keepers, you start to develop an individual technique for your specific team sport. You do not press the shutter and hope for the best. Most team sport professionals seem not to use eye or face detection, because the hit rate is not high enough. No matter which brand.
They neither do "spray & pray". They do not use 40fps. They do not have the time to screen all these images afterwards or with a partner live during the game.
I just want to say with this, that we as amateurs have sometimes the tendency to believe that technology is already good enough and we push the button only. But if the pros are not able to do it, we won't neither. Just buying another camera with a 10% better AF in areas outside of team sport does not help at all.
Professional sports photographers do not "hunt" for an image, they "catch" it. They do not follow the player
over the field all the time (hunter), they know in advance when and where a good situation can happen and they wait at the right standpoint for this shot and then press the trigger (catch). Eye or face detection plays according to these photographers a minor role or no role at all.
I will experiment in the coming weeks more with the AF settings. But the AF incl. face detection of the S5ii and S1Rii is good enough for runners, bicycles etc pp. Only team sport - like with other brands - the AF tracking eye/faces often or sometimes fails, depending on the situation, standpoint, clothes, heads turned down, helmets, other players crossing etc. pp.