Leeds confirmed the 29-year-old Wainuiomata Lions junior - a 2020 Challenge Cup final winner with the Rhinos - had been released from the last year of his contract so he could stay with his daughter.
British reports indicated Seumanufagai had requested a release because travel restrictions during the pandemic would have made it difficult for him to see his child.
"We are sorry to see him leave the club but fully support and understand his decision,'' Leeds' director of rugby Kevin Sinfield said.