Many academic investigations are now examining dark energy theories in conjunction with cosmic strings and scalar fields since these factors play a crucial part in the examination of the present scenario characterised by the universe’s accelerated expansion. A non-static plane-symmetric Tsallis holographic dark energy model is developed in the presence of an attracting massive scalar field and cosmic strings. This paper presents a deterministic solution to the Einstein field equations, using conditions that are both mathematically and theoretically relevant. The model’s cosmic dynamical parameters have been determined, including the energy conditions, deceleration parameter (q), statefinders, equation of state parameter (ωde), stability analysis, r – q plane, and ωde – ω’de plane. We have also highlighted their physical significance in the description of our model. Given the current observations, observational bounds of cosmological parameters are included. Our dark energy model appears to correspond with recent cosmological findings.