From what I can tell

Male MC's wearing Karna's outfit
Female MC's wearing Gawain's
Saber's wearing Julius'
Archer is wearing Caster's
Caster is wearing Archer's
Gil(?)'s wearing Rani's
Rani's wearing Rin's
Rin's wearing Jinako's (surprised the pants could stay on as I don't think Rin has the hips Jinako does)
Gawain's wearing the female MC's
Leo's in Saber's outfit
Julius is in the Male MC's
Jinako is in Leo's (horribly snug fit i'd say)
and Karna's wearing Gil's.