  We present extensive photometric and spectroscopic observations of the
peculiar Type Ia supernova (SN Ia) 2022vqz. It shares many similarities with
the SN 2002es-like SNe Ia, such as low luminosity ($M_{B,\rm
max}=-18.11\pm0.16$ mag) and moderate post-peak decline rate ($\Delta
m_{15,B}=1.33\pm0.11$ mag). The nickel mass synthesised in the explosion is
estimated as $0.20\pm0.04~{\rm M}_\odot$ from the bolometric light curve, which
is obviously lower than that of normal SNe Ia. SN 2022vqz is also characterised
by slowly expanding ejecta, with Si II velocities persisting around 7000 km
s$^{-1}$ since 16 days before peak brightness, unique among all known SNe Ia.
While all of these properties imply a lower-energy thermonuclear explosion that
should leave a considerable amount of unburnt materials, the absent signature
of unburnt carbon in spectra of SN 2022vqz is puzzling. A prominent early peak
is clearly detected in the ATLAS $c$- and $o$-band light curves and in the ZTF
$gr$-band data within days after the explosion. Possible mechanisms for the
early peak are discussed, including the sub-Chandrasekhar-mass
double-detonation model and interaction of SN ejecta with circumstellar
material. We find that both models face some difficulties in replicating all
aspects of the observed data. As an alternative, we propose a hybrid C-O-Ne
white dwarf as the progenitor of SN 2022vqz; it can simultaneously reconcile
the tension between low ejecta velocity and the absence of carbon. We further
discuss the diversity of SN 2002es-like objects and their origin in the context
of different scenarios.
