A group
$G=AB$ is the weakly mutually permutable product of the subgroups A and B, if A permutes with every subgroup of B containing
$A \cap B$ and B permutes with every subgroup of A containing
$A \cap B$. Weakly mutually permutable products were introduced by the first, second and fourth authors [‘Generalised mutually permutable products and saturated formations’, J. Algebra 595 (2022), 434–443] who showed that if
$G'$ is nilpotent, A permutes with every Sylow subgroup of B and B permutes with every Sylow subgroup of A, then
$G^{\mathfrak {F}}=A^{\mathfrak {F}}B^{\mathfrak {F}} $, where
$ \mathfrak {F} $ is a saturated formation containing
$ \mathfrak {U} $, the class of supersoluble groups. In this article we prove results on weakly mutually permutable products concerning
$ \mathfrak {F} $-residuals,
$ \mathfrak {F} $-projectors and
$\mathfrak {F}$-normalisers. As an application of some of our arguments, we unify some results on weakly mutually
$sn$-products.