The French national team may be the iciest in all of sports ... 'cause fresh off getting championship rings from Paul Pogba, star defender Lucas Hernandez got a World Cup trophy chain!!
TMZ Sports has learned ... Lucas is following his teammates' lead in commemorating their 2018 World Cup with diamonds -- copping 2 tennis chains and a pendant of the World Cup trophy.
We're told Hernandez hit up Antonio Brown's go-to guy, Gabriel the Jeweler, for the job ... and whipped up the chains with 30 carats each, and the white gold trophy with 6 carat diamonds.