The #SFGiants have had an active dialogue with Lorenzo Cain of late, and that’s not likely to change with McCutchen trade. Ideally, Giants would like to play McCutchen in a corner spot. As @hankschulman observed, the question is how far they’re willing to go on on deal with Cain.
Sources say the #SFGiants rank the non-Lorenzo Cain free agent CF options as: 1) Jarrod Dyson; 2) Jon Jay; 3) Cameron Maybin. Dyson is valued for speed, defensive metrics and SB ability. Giants have expressed interest, but Dyson still talking to multiple clubs. Nothing imminent.
The #SFGiants don't appear to have ruled out Andrew McCutchen in center. But he has a minus-65 Defensive Runs Saved in CF since 2014, and the NL West has some spacious outfields. Steven Duggar is an internal option for CF, but he has only 289 ABs above Class A ball.
The #SFGiants have also been on Billy Hamilton for a while, but they've taken a bite out of their farm system with Longoria and McCutchen trades, and owner Bob Castellini's personal fondness for Hamilton makes him tough to pry loose from the #Reds.