Does the mac mini work with a USB-C dock
Will the Mac mini work with a USB-c dock connected to two external monitors?
What year model Mac Mini and what external Displays?
The 2018 Mac mini supports three displays. 1 display on the HDMI port and 2 displays staggered on the USB-C ports.
The 2020 M1 Mac mini only supports two displays. 1 display on the HDMI port and 1 display on a USB-C port.
see > Connect a display to Mac mini - Apple Support
While some multi port docks may support 2 displays from one of the Mac mini's USB-C ports, they will only be in Mirroring Mode and not in Extended Desktop Mode.