Men must not see your feet without socks. The most authentic opinion is that she must also cover her feet when praying.

Kindly refer to the following link(s):

Praying in transparent socks for women


Is it Compulsory for Women to cover their feet while praying?


Transparent socks or socks with holes: can we go out, wipe over or pray with them?


Must women cover feet when praying? If shape of feet is seen with socks, prayer valid?


Can a woman pray with her feet uncovered?


Also see: Ruling on covering the hands & face in prayer for women