Ireland fast bowler Josh Little also included and England spinner Sophie Ecclestone making the women's side.
The ICC kicked off its 2022 awards, which will be announced over the next four days, by unveiling its 20-over XIs.
England's white-ball captain Buttler is named as captain of the men's team, having led his country to the format's top prize a matter of months after taking the reins from the retired Eoin Morgan, while all-rounder Curran was a straightforward pick after being named player-of-the-tournament for his outstanding displays in Australia.
Left-arm seamer Little flies the flag for Ireland after a breakout year that saw him finish as second highest wicket-taker with 39.
Of the five English women who made the cut in 2021, spinner Ecclestone is the only one to hold on to her place. The slow left-armer is ranked number one T20 bowler in the world and earns her place in a side featuring four Indians and three Australians.
Men's T20 team of the year: Buttler (Eng, c, wk), Rizwan (Pak), Kohli (Ind), Yadav (Ind), Phillips (NZ), Raza (Zim), Pandya (Ind), Curran (Eng), Hasaranga (SL), Rauf (Pak), Little (Ire).
Women's T20 team of the year: Mandhana (Ind), Mooney (Aus), Devine (NZ, c), Gardner (Aus), McGrath (Aus), Dar (Pak), Sharma (Ind), Ghosh (Ind), Ecclestone (Eng), Ranaweera (SL), Singh (Ind).