Hydrangeashydrangeas.com has detailed info on most hydrangea topics and can now be found here:

https://plantaddicts.com/all-about-hydrangeas

However, I was not sure I understood "the" question. Can you rephrase it? Do you want information on changing your blooms from what current color to which new color? Or are you trying to get a shrub like Bloomstruck, one that can produce blooms of several shades in just one shrub?

If you do not mind, please let us know where you are and your zone?

Part of what determines a hydrangea’s color is genetics, both the particular species of Hydrangea and also the particular cultivar. Some species are sensitive to soil pH in determining color, but 3 of the 5 common species aren’t. So we need to know what kind of Hydrangea you have, both species and cultivar. Do you have either a tag and/or a photo? Also, as far as mixed colors on one plant, most often that is determined by a combo of genetics and aging of flowers.

You wouldn’t typically have pink and blue on the same plant, though some unethical nurseries may show photoshopped images of that. Generally flowers on colored big-leafed hydrangeas will tone towards pink if the soil is basic or lacks available aluminum and be blue if the soil is acidic and has available aluminum. You can buy supplements to add that will make soil more acid and will add aluminum.

Other mixed color blooms such as on H. macrophylla Pistachio ‘Horwack’ or H. Pinky Winky have mixed flower colors based on genes.

The first and last photos might well just have flowers that are fading, and the middle one has lighter colored flowers that are just starting to open.

I would suggest planting your hydrangeas in the garden and watching to see what color the blooms are in that spot. Hydrangea colors can be very variable depending many factors. Color can depend on soil, sun exposure, ph of soil and the genetics of the plant. I propagate hundreds each season and I can plant a clone of a plant in two different spots in the garden and get different colored blooms. You can chose to try to control the color but it is a challenging pursuit. Most change colors depending on the age of the bloom - almost like magic. To me the charm of the plant is this property. Some will change slowly and others seem to change daily. I have one Ayesha that is blue while a clone of the same plant is pink although it is only about 30 feet away from the mother plant. If the color is really important to you then you should buy the plant from a grower near your location with a guarantee that the plant can be returned if not as advertised. If you buy your plant from a box store, then there is no way to be sure that the color will be as listed on the tag. Potted florist hydrangeas bought in grocery stores and box have been grown for a particular color - most potting soils will produce pink blooms, I guess they sell better, and when they are planted in the garden they can turn blue.

Most hydrangeas eventually turn blue in my garden under the canopy of fir trees while under the maples in the front garden, there are more pinks.

Some plants are listed as 'not dependent on ph of soil for color' or something like that and those may be better if you have to have a specific color in mind.