Courtney Siobhan Mairad Regan, aged 24, of Snaefell Road, and Samantha Dunn, aged 29, of Watterson Close, appeared at Douglas Courthouse on Tuesday, August 13.
They are accused of punching, kicking, and biting their alleged victim on April 7 at Ms Dunn's home.
Ms Regan was represented in court by advocate Victoria Kinrade, while Ms Dunn was represented by Emily Brennan.
The two defendants will appear at the Court of General Gaol Delivery on a date to be set.
A separate charge, of provoking behaviour, against Ms Regan, was withdrawn.
Bail continues for both parties.