Kone, a Mali youth international, spent the second half of last season with the Swiss Super League club and made a positive impression during that spell, gaining valuable experience in senior football.
He now returns to Switzerland to continue his development, having originally joined United from Guidars FC in his homeland back in August 2024 as one of the club's most promising young midfield prospects.
Lausanne finished ninth in the Swiss Super League last season and will be hoping to progress further this term following the July appointment of new head coach Luka Elsner, with Kone expected to feature regularly as he continues his development away from Old Trafford.
Manchester United, meanwhile, are considering a move for Danilo, according to the BBC, with the Brazil international added to the club's shortlist of transfer targets as it looks to strengthen in midfield.
Newcastle United are also credited with interest in the 25-year-old, while his current club Botafogo have already received offers of around £25m from both Palmeiras and Zenit St Petersburg as they weigh up his next move.
Danilo made 62 appearances across all competitions during three seasons at Nottingham Forest, the last of which began with him breaking his leg on the opening weekend of the Premier League season.
He has since returned to his best form back in Brazil, featuring prominently for his country at the World Cup and impressing enough to attract fresh interest from clubs back in England. Botafogo are said to be keen to sell the midfielder abroad rather than back to Palmeiras, the club he left for Forest in 2023, leaving both United and Newcastle to monitor closely how his situation develops in the coming weeks as the transfer window enters its final stretch before the new Premier League season gets under way.