"Sometimes the Prophet ﷺ would walk in one sandal."  

رُبَّمَا مَشَى النَّبِيُّ ﷺ فِي نَعْلٍ وَاحِدَةٍ  

From his father, about 'Aishah that: "She would walk in one sandal." This is more correct.  

أَنَّهَا مَشَتْ بِنَعْلٍ وَاحِدَةٍ وَهَذَا أَصَحُّ