What kind of color film? Reversal chromogenic, negative chromogenic or reversal dye bleach are all of the common types. Within those, the dye forming materials may be oil or water based. So lets try to get more specific.
I have already posted the results of a single layer dye bleach based color coating. It requires a sliver halide emulsion with a green sensitizer and a magenta azo dye. The dye must be mordanted in place by some means, or be ballasted in place.
I have also posted generic and specific methods for making the oil soluble dispersions for use in color chromogenic coatings.
You need the coupler and the silver halide in that case. If you go with water soluble couplers you need either a ballasted coupler or a mordant.
I can create all 3 color imaging layers but cannot make yellow filter layer as of yet. I have no couplers, but I do have yellow and magenta azo dyes. I have no cyan azo dye.
The real problem will be coating the required layers by hand. This will nominally be 6 layers or more for any decent imaging. My yield handcoating multilayers at EK was on the order of 30% or less due to defects in the coating process, but those that I got imaged very well. Any given single layer gave a yield of 90% or more.