No indication of semantic not phonetic difference for these two characters is found.
This description is not repeated here.
- https://en.wikipedia.org/wiki/Radical_157 Radical 157 or radical foot (足部) meaning "foot" is one of the 20 Kangxi radicals (214 radicals in total) composed of 7 strokes. In the Kangxi Dictionary, there are 580 characters (out of 49,030) to be found under this radical. 足 is also the 158th indexing component in the Table of Indexing Chinese Character Components predominantly adopted by Simplified Chinese dictionaries published in mainland China. Radical 157 (U+2F9C) .. 足 (U+8DB3) "foot" ..