In this work nanostructured silicon, silicon nanotubes (SiNTs) and porous silicon (PSi), with embedded hard magnetic FePt nanoparticles (NPs) is used as platform to create hard magnetic nanomagnet-arrays. The magnetic response of FePt-loaded composite materials is investigated, which have potential in high-performance magnets and as rare earth magnet alternatives. PSi/FePt demonstrates superior hard magnetic behavior with a higher coercivity and remanence compared to SiNTs/FePt. Varying the Fe:Pt molar ratio in deposits results in a small coercivity (HC) change. FePt-loaded samples consistently show increased coercivity and remanence compared to Co-loaded samples, with PSi exhibiting a stronger effect compared to SiNTs. Comparing FePt-loaded samples with Co-NP-loaded samples, in both template types an increase of the coercivity is observed for FePt. Also in the case of Co-loading the utilization of PSi offers higher coercivities compared to SiNTs. From the investigated composite systems the ones consisting of PSi and FePt offer the highest energy product.