  SN 2020cxd is a representative of the family of low-energy, underluminous
Type IIP supernovae (SNe), whose observations and analysis were recently
reported by Yang et al. (2021). Here we re-evaluate the observational data for
the diagnostic SN properties by employing the hydrodynamic explosion model of a
9 MSun red supergiant progenitor with an iron core and a pre-collapse mass of
8.75 Msun. The explosion of the star was obtained by the neutrino-driven
mechanism in a fully self-consistent simulation in three dimensions (3D).
Multi-band light curves and photospheric velocities for the plateau phase are
computed with the one-dimensional radiation-hydrodynamics code STELLA, applied
to the spherically averaged 3D explosion model as well as spherisized radial
profiles in different directions of the 3D model. We find that the overall
evolution of the bolometric light curve, duration of the plateau phase, and
basic properties of the multi-band emission can be well reproduced by our SN
model with its explosion energy of only 0.7x10^50 erg and an ejecta mass of 7.4
Msun. These values are considerably lower than the previously reported numbers,
but they are compatible with those needed to explain the fundamental
observational properties of the prototype low-luminosity SN 2005cs. Because of
the good compatibility of our photospheric velocities with line velocities
determined for SN 2005cs, we conclude that the line velocities of SN 2020cxd
are probably overestimated by up to a factor of about 3. The evolution of the
line velocities of SN 2005cs compared to photospheric velocities in different
explosion directions might point to intrinsic asymmetries in the SN ejecta.
