The deal was first reported Tuesday by Newsday, which also reported that Maxwell's contract is pending a physical and coronavirus intake testing.
Maxwell hasn't played in the majors since 2018 with the Oakland Athletics. He was the first major league baseball player to kneel during the national anthem to protest social injustice; that was in 2017, after President Donald Trump's comments that NFL players who knelt should be "fired."
In a story by ESPN's Howard Bryant published earlier this month, Maxwell said he was still "bitter as f---" over the lack of support he received from MLB players and general managers at the time.
"The season's gonna resume. They're going to get more fame because it's going to look like they're standing up for what's right," Maxwell said in the ESPN story. "They're making T-shirts and they're showing they care, but they don't go back to the original sacrificed person. Where was all of this then? It's easy to talk because everyone's talking. I was out there by myself. I'm bitter as f---, and I'm not hiding it."
Maxwell, his agent and Athletics president Billy Beane also acknowledged in the story that Maxwell declined an opportunity to return to the A's in spring training this year before the coronavirus pandemic.
In July 2018, Maxwell was sentenced to two years of probation on a disorderly conduct charge stemming from a gun-related incident in Arizona.
Maxwell, 29, spent 2019 with Acereros de Monclova of the Mexican League, batting .325 with 24 home runs and 112 RBIs in 109 games.
The Associated Press contributed to this report.