My son does football, soccer, and basketball, daughter does soccer and gymnastics. Both kids are under 10 so they don't have to wear masks at school, etc.
Soccer - There was one kid whose parents sent him initially with a mask, no one else wears them and the kid would take his off about 1 minute after running on the field. That only lasted a game or two. Parents hang out on the sidelines like normal, 95% of the kids do in person school. Usually no shaking hands after the game, they line up and wave instead. Walking around the fields you'll see a few parents with a mask here or there but it isn't widespread. Feels pretty much like 2019 which is great
Football - See soccer. 50% of my son's soccer team is on his football team. They took the bleachers away so you had to bring your own chair if you wanted one
Basketball - The facility has pretty strict attendance limits (1 parent per player, no siblings, etc.). No masks required for players. Parents must mask up the entire time and the team will get a technical called on them if a parent doesn't have their mask on or is wearing it improperly. I don't know for a fact but I suspect that the refs are encouraged to not blow their whistles as much as you essentially need to commit attempted murder to get a foul this year
Gymnastics - No masks for participant, can have as many watchers as you want but they have to wear a mask if over 10.