Multifunctional electronic systems rely indispensably on high quality-factor (Q) micro- and nano-electro-mechanical systems (M/NEMS) resonators for frequency control applications such as precise clock generation, synchronization, and radio-frequency wireless communication. Hundreds of high-performance M/NEMS resonators with frequencies extending over 32 kHz to 6 GHz are heterogeneously integrated with complementary metal oxide semiconductor (CMOS) circuits to form portable frequency control systems. However, heterogeneous integration imposes substantial overhead on critical system specifications, such as size and power consumption, as well as overall performance. This further limits system scalability for dynamic spectrum use and frequency extension to untapped bands in centimeter- and millimeter-wave regimes. Here, we present intrinsically switchable NEMS resonator building-blocks with ultra-wide-spectrum coverage for monolithic CMOS integration of frequency control systems, using superlattice hafnia-zirconia-alumina (Hf0.5Zr0.5O2 – Al2O3) transducers. The superlattice structure along with ferroelastic re-orientation through pulsed poling enable large linear electromechanical coupling (kt2) and high-Q in Hf0.5Zr0.5O2 – Al2O3 NEMS resonators, operating in lateral- and thickness-oriented bulk acoustic wave modes. Integrated NEMS resonators with frequencies (f) over 0.4 to 17.3 GHz, f-Q products up to 4.04×1012 and kt2s as high as 2.5%, are demonstrated by electrical measurements. Using DC bias voltage for depolarization of transducers, we show these resonators can be intrinsically switched off to their electromechanical noise floor, providing an on-off isolation as high as 37dB. Intrinsically switchable superlattice hafnia-zirconia-alumina NEMS resonators pave the way to realize switch-free, monolithic frequency control systems with multi-band operation towards mm-wave regime.