O'Keefe, who played 286 games for the Swans and was an integral member of the club's 2005 and 2012 premiership sides, will serve as a development coach while also assisting the midfield.
Teague will replace Mark Bickley as coach of the forward line. Bickley has advised the Crows he would like to pursue other opportunities in 2015 but he will remain at the club in a marketing and promotional role.
Teague played 83 AFL games and coached alongside Walsh at the Eagles before joining the Saints.
Walsh chases his dreams at Adelaide
Walsh said his relationship with Teague, and O'Keefe's success at the highest level would ensure they became important members of the coaching staff.
"Ryan is a quality person who comes from a successful environment," Walsh said.
"His leadership and knowledge gleaned from an outstanding playing career at Sydney will be invaluable.
"David and I developed a strong rapport while working together at the Eagles for three years.
"He is a talented and astute young coach who will be an influential part of our team."
Scott Camporeale, Darren Milburn and Matthew Clarke will continue as midfield, defence and ruck coaches.
Twitter: @AFL_Harry