I've seen some microinverters with multiple inputs. This one has four inputs allowing 4 panels: https://www.vevor.com/grid-tie-solar-inverter-c_10762/solar-grid

I've seen some microinverters with multiple inputs. This one has four inputs allowing 4 panels: https://www.vevor.com/grid-tie-solar-inverter-c_10762/solar-grid-tie-micro-inverter-dc-22-50v-to-ac-110v-compact-pure-sine-mppt-p_010970615651 https://www.vevor.com/grid-tie-solar-inverter-c_10762/solar-... Additionally: microinverters can support higher voltages, so you can just hook them up in series. It's also possible to use an adapter to hook them up in parallel.