Can I use different colors on the legend text for the title, group and object? If yes, how do you do it? My QGIS version is 2.14.12-Essen.
Unfortunately there is only one color option shared for all texts in the legend. If you need different colors probably the best option is to use combination of text fields (labels) and/or one or more legends depends on what works better for you.
As far as I am aware there is no request for this either so you might file it and hope somebody will like to add this feature for you: