They cost 0 and add a coloured mana
That said, the biggest names in football are well-represented Mahomes, Stroud, Caleb Williams, Harrison Jr., and other top talent all have a chance to show up
Obviously replacing some of the most effective draw spells in Magic isn't easy, but with a little effort you can find cards that will mimic those abilities and even sometimes turn out to be better
The current two most common examples, however, are Tornadus EX (who does more damage if theres a Stadium in play) and Terrakion NVI (who does more damage if a Pokmon on their side of the field was KOd)
It is still a creature spell, of that name, with the CMC of the original card (not the mutate cost)
Suffice it to say that, as cEDH games have gotten slower and players more content to wait turns out, just about every deck has got an engine up its sleeve