Last week, it was confirmed that Stephenson would be exiting Saints this summer and he will now look to sign off by helping the Wanderers continue their defence of the Prem Rugby A League title.
The centre is part of another strong second-string back line, which also includes Tom Collins, Ken Pisi and England Under-20s players James Grayson and Fraser Dingwall.
There are two further England Under-20s aces in the pack, with props Toby Trinder and Ehren Painter both starting.
Reece Marshall, who scored in the Wanderers' most recent victory, against Worcester, will pack down at hooker.
Alex Moon and James Craig, who makes his return from injury, start in the second row.
Mitch Eadie and Lewis Ludlam are given an opportunity in the back row, with 19-year-old flanker Paddy Ryan completing Northampton’s starting line-up.
The Wanderers will be looking to extend their perfect record in this year’s Premiership Rugby A League.
So far, they have racked up eight bonus-point wins from as many matches.
Wanderers: Furbank; Pisi, Dingwall, Stephenson, T Collins; Grayson, Mitchell; Trinder, Marshall, Painter; Moon, Craig; Ludlam, Ryan, Eadie.
Replacements: Clare, Beesley, M Collins, J Onojaife, D Onojaife, Kessell, Estelles, Elliott.
Wasps A: James; Moor (Oxford Univ), Anderson, Eastgate, Goble (Nottingham); Jardine (Dulwich College), Hampson (c); Thornton, Oghre, Stuart; Garratt, Jubb (Coventry); Curran, Seabrook, Willis.
Replacements: Thompson (Bishop Burton College), Higgins (Coventry), Doran Jones, Gray (Coventry), Salt (Hinckley), Owen, Porter, Palmer (Coventry)