A basic funnel, no bells or whistles. Completely customizable using the OpenSCAD or Thingiverse customiser. Any size, with some options.

You can add a hook hanging tab. You can add a collar that allows the funnel to set on top of a bottle.

NOTE: The Thingiverse customizer doesn't support Boolean variables, which are used in the source to turn on/off the tab and collar. Set the tab width to zero or the collar diameter to zero to disable those features. By default, they are both "on" but the collar diameter is set to zero initially to disable the collar. Set its value to the outer diameter of your bottle to turn the collar on

OpenSCAD source included. The customizer in OpenSCAD works better thatn Thingiverse.

Support usually won't be needed.

+4h Updated: enabled the collar in the SCAD file otherwise there'd be no way to use it in the Thingiverse customizer.