The Hurricanes traded Williams to Los Angeles for O'Sullivan and a second-round pick in this year's draft. Carolina then sent O'Sullivan and its own second-round pick in Edmonton for Cole and the Oilers' fifth-round draft pick.
In July, Carolina sent Cole to the Oilers for defenseman Joni Pitkanen, parting with one of the team's most popular players who helped them win the Stanley Cup in 2006. Carolina selected Cole in the third round of the 1998 draft.
The 30-year-old Cole has 16 goals and 11 assists in 63 games this season.