In this paper, an Analog and a Digital-Based Operational Transconductance Amplifier (OTA) in a 800 nm Indium-Gallium-Zinc-Oxide (IGZO) Thin-Film Transistors (TFT) Flexible Integrated Circuits (FlexICs) technology are presented and compared on the basis of post-layout simulations. The analog OTA (A-OTA) and the Digital-Based OTA (DB-OTA) occupy a total area of $42,624\mu \mathrm{m}^{2}$ and $25,207\mu \mathrm{m}^{2}$, respectively and - based on post-layout Monte Carlo (MC) simulations on 100 samples operated at 3.3V with 50pF capacitive load - they achieve an average gain-bandwidth product (GBW) of 58 kHz and 86 kHz, respectively, with an average power consumption of $90\mu\mathrm{W}$ and $113\mu \mathrm{W}$. The simulated standard deviation of the input offset voltage is 22.3 mV for the A-OTA and 7.2 mV for the DB-OTA while the input-referred integrated noise over the entire GBW is $8.8\mu \mathrm{V}_{\text{RMS}}$ and $87\mu \mathrm{V}_{\text{RMS}}$ for the A-OTA and DB-OTA respectively.