  We present an optical, X-ray, and $\gamma$-ray study of 1SXPS
J042749.2-670434, an eclipsing X-ray binary which has an associated
$\gamma$-ray counterpart, 4FGL J0427.8-6704. This association has led to the
source being classified as a transitional millisecond pulsar (tMSP) in an
accreting state. We analyse 10.5 years of Fermi LAT data, and detect a
$\gamma$-ray eclipse at the same phase as optical and X-ray eclipses at the
>5$\sigma$ level, a significant improvement on the 2.8$\sigma$level of the
previous detection. The confirmation of this eclipse solidifies the association
between the X-ray source and the $\gamma$-ray source, strengthening the tMSP
classification. However, analysis of several optical data sets and an X-ray
observation do not reveal a change in the source's median brightness over long
timescales or a bi-modality on short timescales. Instead, the light curve is
dominated by flickering which has a correlation time of 2.6 min alongside a
potential quasi-periodic oscillation at $\sim$21 min. The mass of the primary
and secondary star are constrained to be $M_1=1.43^{+0.33}_{-0.19}$ M$_{\odot}$
and $M_2=0.3^{+0.17}_{-0.12}$ M$_{\odot}$ through modelling of the optical
light curve. While this is still consistent with a white dwarf primary, we
favour the transitional millisecond pulsar in a low accretion state
classification due to the significance of the $\gamma$-ray eclipse detection.
