Well I'm not female but I've had my soles licked plus have licked women's soles. General consensus seems to be it depends on how sensitive the soles are and the type of lick. I'm actually quite ticklish but found a long lick with a broad tongue to not bother me in a ticklish way. Using the tip of the tongue, or smaller/quicker licks did. Current and previous partners have pretty much agreed with this but the exact threshold where it becomes overly ticklish (and whether that is good or bad) varied quite a bit. Any other questions? I'm always happy to help the curious.