Our league rules have maximum participation numbers for males and minimums for females. There are no maximums or minimums for non-binary players.
So for instance, indoor volleyball rules have a maximum of 3 males on the court at a time and a minimum of 2 females. So, a team with non-binary players could play with:
3 males, 2 females, 1 non-binary
2 males, 3 females, 1 non-binary
0 males, 3 females, 3 non-binary
(examples, not all combinations are listed)