what's your budget ?

There are a number of options, from a full on connex full colour for a couple of hundred thousand dollars, on down to the xyzprinting davinci for around 3000 pounds: https://www.amazon.co.uk/XYZ-Printin...gateway&sr=8-3

Then there are the other options where you add an external filament mixer to a bog standard i3.
palette 2 from mosaic: https://www.mosaicmfg.com/products/palette-2
starts at $500.