The Pools composition according to Wikipedia
Teams were seeded following the serpentine system according to their FIVB World Ranking as of 29 September 2019.
FIVB reserved the right to seed the hosts as head of pool A regardless of the World Ranking.
Rankings are shown in brackets except the hosts who ranked 7th.
Japan (Hosts); Serbia (3); Brazil (4); South Korea (9); Dominican Republic (10); Kenya (19)
China (1); United States (2); Russia (5); Italy (8); Argentina (11); Turkey (12)
samusama made the almost correct prediction about the pool distribution in Oct 2019, with exception it's Kenya i/o Cameroon that will play in Tokyo: