  In this work we study the formation of the first two black hole-neutron star
(BHNS) mergers detected in gravitational waves (GW200115 and GW200105) from
massive stars in wide isolated binary systems - the isolated binary evolution
channel. We use 560 BHNS binary population synthesis model realizations from
Broekgaarden et al. (2021a) and show that the system properties (chirp mass,
component masses and mass ratios) of both GW200115 and GW200105 match
predictions from the isolated binary evolution channel. We also show that most
model realizations can account for the local BHNS merger rate densities
inferred by LIGO-Virgo. However, to simultaneously also match the inferred
local merger rate densities for BHBH and NSNS systems we find we need models
with moderate kick velocities ($\sigma\lesssim 10^2\,\rm{km}\,\rm{s}^{-1}$) or
high common-envelope efficiencies ($\alpha_{\rm{CE}}\gtrsim 2$) within our
model explorations. We conclude that the first two observed BHNS mergers can be
explained from the isolated binary evolution channel for reasonable model
realizations.
