Fans on the Capcom Unity forums speculate that Fong Ling, a Chinese agent from Gun Survivor 4: Dead Aim, may appear in Resident Evil 6.
As part of RE6 takes place in China, they speculate that Fong Ling, who's described as China's best counter-terrorist agent, might make an appearance in the game—perhaps even as Chris's partner.
From what we can tell, the events of Dead Aim are canonical in the Resident Evil series. However, I personally doubt that Capcom will revisit the niche title, much less include the character in their upcoming game, especially if they can create new characters in their place.