The Ultimate Fighting Championship has yet to confirm the pairing and did not immediately respond to attempts to verify the matchup.
Should the bout become official as expected, it would likely be a title-fight eliminator to face the winner of 145-pound champions Jose Aldo and Conor McGregor (interim), who will seek to unify the UFC featherweight titles the following day on Dec. 12 in Las Vegas.
Edgar (19-4-1) last saw action in an impressive unanimous decision victory over Urijah Faber on May 16 and has reeled off four-straight wins. Mendes (17-3) has lost two of three, with defeats against both Aldo and McGregor.