Maxwell returned to Birmingham City in time to be part of the Birmingham reserve team that lost the 2016 Birmingham Senior Cup final to National League North champions Solihull Moors. Maxwell appeared for Birmingham's first team in 2016 pre-season, and by the new year was the under-23 team's joint-highest appearance maker, but had not played a competitive first-team match. On 27 January 2017, he joined League Two club Grimsby Town on loan to the end of the season. At the time, he was receiving treatment for a groin injury at his parent club, so did not make his Football League debut until 18 February, as an 83rd-minute substitute in a 3–0 win against Mansfield Town. On 4 May 2017, Maxwell returned to Birmingham prior to the final game of the season from his loan spell at Grimsby. Maxwell joined National League club Gateshead on a three-month loan on 15 September 2017. He finished the spell with eleven appearances, eight in the league and three in the FA Cup. He joined another National League club, Solihull Moors, in July 2018 on loan until 5 January 2019. He was a first-team regular for the full length of his loan spell, making 23 National League appearances and a further 5 in cup competitions. When the loan expired, Maxwell signed for Solihull Moors on an 18-month contract with an option of a further year. Maxwell joined National League North club Gloucester City on 31 December 2019 on loan for a month. He made his debut the following day in the starting eleven for a 2–1 win at home to Leamington, and made four more appearances before returning to his parent club. Individual