  Superresolution is one of the key issues at the crossroads of contemporary
quantum optics and metrology. Recently, it was shown that for an idealized case
of two balanced sources, spatial mode demultiplexing (SPADE) achieves
resolution better than direct imaging even in the presence of measurement
crosstalk [Phys. Rev. Lett. 125, 100501 (2020)]. In this work, we consider
arbitrarily unbalanced sources and provide a systematic analysis of the impact
of crosstalk on the resolution obtained from SPADE. As we dissect, in this
generalized scenario, SPADE's effectiveness depends non-trivially on the
strength of crosstalk, relative brightness and the separation between the
sources. In particular, for any source imbalance, SPADE performs worse than
ideal direct imaging in the asymptotic limit of vanishing source separations.
Nonetheless, for realistic values of crosstalk strength, SPADE is still the
superior method for several orders of magnitude of source separations.
