Uncapped Romario Shepherd, who is a right-arm pacer and is a handy lower-order batsman has also found a place in the ODI squad.
King, the 24-year-old opening batsman who was a ninth-round pick in the CPL draft, took the tournament by storm smashing 496 runs to lead Amazon Guyana Warriors' unprecedented 11-match winning streak, which was eventually snapped in the final by the Barbados Tridents.
Walsh made his debut for United States of America in 2018 and worldwide debut for them earlier this year, and will now get to represent a new-look West Indies side. Kieron Pollard has expectedly been named the captain of the limited overs teams, but former T20I captain Carlos Brathwaite could not find a spot in any of the squads.
Walsh, meanwhile, who has already played an ODI and eight T20 Internationals for the United States, also made his mark in the recent CPL with 22 wickets to be adjudged Man-of-the-Series for eventual champions Barbados Tridents.
On the other hand, King was the top scorer in the competitionwith 496 runs in 12 innings at a strike-rate of almost 150.
The squads for the three formats were revealed on Tuesday and Darren Bravo will not feature in the Test match having managed a combined 47 with the bat across four innings against India in August. His comments during the World Cup caught some of his own team-mates by surprise and his worldwide future continues to be unclear. He is yet to make his ODI debut. He has also been part of West Indies' domestic structure. Simmons last played a T20 for West Indies in June 2017.
Alzarri Joseph, who missed the bus to World Cup 2019 due to an injury during IPL, is back and has been included in all three formats.
Kieron Pollard (Captain), Shai Hope, Evin Lewis, Shimron Hetmyer, Sunil Ambris, Nicholas Pooran, Brandon King, Roston Chase, Jason Holder, Hayden Walsh Jr., Khary Pierre, Sheldon Cottrell, Keemo Paul, Romario Shepherd, Alzarri Joseph.
T20 squad: Kieron Pollard (captain), Nicholas Pooran, Evin Lewis, Shimron Hetmyer, Sherfane Rutherford, Brandon King, Fabian Allen, Jason Holder, Hayden Walsh, Lendl Simmons, Khary Pierre, Sheldon Cottrell, Denesh Ramdin, Kesrick Williams, Alzarri Joseph.