  The purpose of this work is to investigate some interesting features of a
static anisotropic relativistic stellar object composed of two different types
of fluid distributions typically termed as quark matter (QM) and ordinary
baryonic matter (OBM) together with Krori-Barua type (KB) {\em ansatz} in the
regime of modified $f(\mathcal{G})$ gravity, where $\mathcal{G}$ being the
Gauss-Bonnet invariant term. In order to explain the correlation between
pressure and matter density for the quark matter distribution within the
compact object, we have taken into consideration the well-known MIT bag
equation of state (EoS) whereas there is a simple linear correlation between
pressure and matter density for ordinary baryonic matter. Furthermore, using
graphical representations for varying parameters, the physical credibility of
our obtained solutions has been intensively examined by regularity checking of
the metric coefficients and matter variables, energy conditions, mass function,
and causality conditions. For these analyses, we consider a particular compact
stellar candidate 4U 1538-52. Finally, we found that the resulting outcome
depicts the viability of the considered hybrid stellar model.
