Ryan returns to the ring after September’s contentious split-decision draw in a unification bout against American Jessica McCaskill in Orlando.
Harper is the current WBA light-middleweight champion, having also previously been a champion at super-featherweight. She is also coming off a draw, with Cecilia Braekhus in October.
Also on the card at Sheffield’s Utilita Arena, the undefeated and highly-rated light-welterweight Dalton Smith will take on three-time world-title challenger Jose Zepeda.
The following month Warrington’s pharmacist-turned-boxer Dixon – who is trained by former world champion Anthony Crolla – challenges for a world title in just her 10th outing against Carabajal.
The Argentine’s loss in 22 fights was to pound-for-pound star Katie Taylor, who has since vacated her lightweight title.
In the main event at Manchester’s AO Arena, super-featherweight Jordan Gill – who stopped Ireland’s Michael Conlan in a career-best win in December – continues his charge towards a world title shot by taking on Zelfa Barrett.
