We don't have official information at this time, however we fully expect some characters from Redemption
to make an appearance in Red Dead Redemption 2. If the game is a prequel - which appears to be the case (see below) - then we have no choice but to believe that we'll be rolling with John Marston's old gang.
Artwork and possible characters
John's Old Gang
Of course we will likely see our friendly federal agents at some point since they were the core of the Red Dead Redemption story:
Archer Fordham and Edgar Ross
And if John Marston is involved with Red Dead Redemption 2, then we should see his family as well:
Another person of interest for a prequel is Landon Ricketts - the lengendary gunslinger - who could turn up in some way. John had only heard of him before Redemption's timeline:
Who else might we see in the new Red Dead game?