∀ {C : Type u} [inst : CategoryTheory.Category.{v, u} C] {D : Type u'} [inst_1 : CategoryTheory.Category.{v', u'} D]
  {P : CategoryTheory.ObjectProperty C} {Q : CategoryTheory.ObjectProperty D} (e : C ≌ D)
  [inst_2 : Q.IsClosedUnderIsomorphisms] (h : Q.inverseImage e.functor = P),
  (e.congrFullSubcategory h).counitIso =
    (Q.fullyFaithfulι.whiskeringRight Q.FullSubcategory).preimageIso (Q.ι.isoWhiskerLeft e.counitIso)