In re: Negro League players, Allan and I figured out a reasonable way to divide these 128 all-stars across the decades, So yes, they WILL be included in the 20th century contests (as they should be)!
if we allow relief pitchers from 76-2015 to play in the 00-09 league there are enough to satisfy the roster needs. maybe we could use only those carded from 2010-2015 who were active in 09 or prior this would take some research