<p>We investigate the reconstruction of the Sharma-Mittal holographic dark energy (HDE) model within the framework of <InlineEquation ID="IEq3"> <EquationSource Format="TEX">\(\mathcal {F(Q)}\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mi mathvariant="script">F</mi> <mo stretchy="false">(</mo> <mi mathvariant="script">Q</mi> <mo stretchy="false">)</mo> </mrow> </math></EquationSource> </InlineEquation> gravity, where <InlineEquation ID="IEq4"> <EquationSource Format="TEX">\(\mathcal {Q}\)</EquationSource> <EquationSource Format="MATHML"><math> <mi mathvariant="script">Q</mi> </math></EquationSource> </InlineEquation> is the non-metricity scalar. Employing various scalar field models, including quintessence, k-essence, tachyon and dilaton, we reconstruct the corresponding scalar fields and derive their potential, kinetic, and total energies. The evolution of these energy components is analyzed, revealing that the models can successfully describe the late-time accelerated expansion of the universe. In particular, the tachyon reconstruction allows the crossing of the phantom divide (<InlineEquation ID="IEq5"> <EquationSource Format="TEX">\(\omega =-1\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mi>ω</mi> <mo>=</mo> <mo>-</mo> <mn>1</mn> </mrow> </math></EquationSource> </InlineEquation>), while the quintessence and k-essence fields exhibit smooth and physically consistent energy evolution. Our results demonstrate that the Sharma-Mittal HDE in <InlineEquation ID="IEq6"> <EquationSource Format="TEX">\(\mathcal {F(Q)}\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mi mathvariant="script">F</mi> <mo stretchy="false">(</mo> <mi mathvariant="script">Q</mi> <mo stretchy="false">)</mo> </mrow> </math></EquationSource> </InlineEquation> gravity provides a viable framework for modeling dark energy, highlighting the role of generalized entropy in shaping cosmic dynamics and offering insights beyond standard General Relativity.</p>