Comparison of the $\pT$-differential $v_2\lbrace {\rm 2PC} \rbrace$ of inclusive muons at forward (left) and backward (right) rapidity in high-multiplicity p--Pb collisions at $\sNN = 8.16$ \TeV, extracted with the two-particle correlation method with previous measurements performed in p--Pb collisions at \fivenn for inclusive muons  and electrons from heavy-flavour hadron decays .