Steve reported on Twitter that you can match-up players in defensive coverage by overall rating in Madden NFL 18. This means that your top rated CB will match up with the top rated WR from the other team on defense. There's also other options in coaching adjustments for defense to auto-flip your defensive play call, playing ball in the air defense, option defense, and your pass rush.
No word on the available options here other than the ones shown.
https://twitter.com/Steve_OS/status/873675922943217665
Update: Clint Oldenburg chimed in on Twitter to give a more detailed list of ways you can match up with cornerbacks. Included are height, speed, jumping ability and more.
https://twitter.com/ClintOldenburg/status/873734287807225857
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