Choosing a flattering palette without guessing

I have a colour consultation booked soon, and I am considering a change from my natural dark blonde. I would like something slightly softer around my face, not a dramatic transformation that needs constant maintenance. The reference pictures I saved move between soft-summer beige blonde, and each one seems convincing under different lighting. I tried some virtual colour swatches, but the screen often smooths away redness. That makes every option look more successful than it might be outside the app. My biggest concern is mistaking a flattering filter for a flattering colour. I took one set of pictures in the bathroom mirror and kept my hair, clothes, and camera settings unchanged. To compare the cooler families, I checked hair color analysis as a way to label the options. I am now leaning toward keeping the base and cooling the ends, provided the stylist agrees after seeing my hair in person. I will also ask for an explanation of the undertone. How do you tell when a preview is changing more than the hair colour?