The deal would reportedly be worth an initial £15 million with an additional £3 million coming courtesy of add-ons. It's understood personal terms are already agreed between James and the Stretford club.
The 20-year-old's rise has been meteoric. In August 2017, Shrewsbury Town sent an on-loan James back to Swansea after he failed to break into the League One club's first team. And Wales Online's Mathew Davies claims James almost signed permanently for Yeovil Town last summer until a deal collapsed. Yeovil will play in the fifth tier for the 2019-20 season.
Now, James is on the verge of becoming a Manchester United player.
The 2018-19 Championship campaign yielded four goals and seven assists in 33 appearances for James, predominantly from his position on the left flank. His rapid dash for Swansea against Brentford in February's FA Cup fifth round captured nationwide attention, and he continued to develop under Graham Potter throughout Swansea's season.
James was handed his Wales debut by Manchester United legend Ryan Giggs in November and further supplemented his burgeoning reputation four months later with a 20-yard finish against Slovakia.
The former Hull City youth teamer almost joined Leeds United in January, but that transfer broke down.