Does anyone know of any font families that 6, 9, 8, 0 look exactly the same upside down as right side up? The 6 upside down would look like 9 and vice-verse. Thanks!
Font’s that are very modular, like Variable, are a good place to look. Anything humanist or old style is going to have too much modulation to fit your requirement.
Case in point, try a search for “modular” at MyFonts and Variable and many others that fit your request come right up.