International makeup chain Sephora is implementing sweeping changes in its merchandising, marketing and employee training practices in one of the most public efforts by a major retailer to mitigate the potential for racial profiling and other discriminatory practices at its stores. The initiative announced Wednesday is the culmination of customer and employee surveys, interviews and academic research that have been underway since 2019. But issues around race and inequality took on new urgency following the summer’s Black Lives Matter protests and the police killing of George Floyd in May, executives said. The chain also has faced backlash from Black shoppers,...