For madden mobile, there are some rostered players you don’t need. So, you can exchange some of each player for the next rarity. Like trade in two in commons for a rare and so on. Thank you.
This system seems plausible as they do this in nba live trade in 5 75 plus get an elite two 81 elites give u an 83 and so on so it should be relatively easy to adjust a trades option with this